Percents - ACT Math

1. Convert 125% to a fraction in simplest form.

   $\frac{5}{4}$. $125\% = \frac{125}{100} = \frac{5}{4}$ in lowest terms.

2. A number is increased by $20\%$ twice. What is the overall multiplier?

   $1.44$. $1.20 \times 1.20 = 1.44$

3. What is 15% of 300?

   45. Calculate $0.15 \times 300 = 45$.

4. What is the percent increase from 60 to 90?

   50\%. Change is 30, divided by original 60, times 100%.

5. What is 25\% of 300?

   75. Convert 25% to decimal (0.25) and multiply by 300.

6. What is 5% of 60?

   3. Calculate $0.05 \times 60 = 3$.

7. What is 30\% of 250?

   75. Convert 30% to decimal (0.30) and multiply by 250.

8. What is the decimal equivalent of $12.5\%$?

   $0.125$. $12.5\% = \frac{12.5}{100} = 0.125$

9. What is 60% of 150?

   90. Calculate $0.60 \times 150 = 90$.

10. How do you convert 0.08 to a percent?

    8\%. Move decimal point two places right to convert to percent.

11. What percent of $60$ is $15$?

    $25\%$. $\frac{15}{60} \times 100\% = 25\%$

12. If 90 is 45% of a number, what is the number?

    200. If $90 = 0.45x$, then $x = 90 \div 0.45 = 200$.

13. What is the percent decrease from 100 to 80?

    20\%. Change is 20, divided by original 100, times 100%.

14. If 50 is 20% of a number, what is the number?

    250. If $50 = 0.20x$, then $x = 50 \div 0.20 = 250$.

15. What is $20\%$ of $45$?

    $9$. $0.20 \times 45 = 9$

16. What is 200% of 50?

    100. Calculate $2.00 \times 50 = 100$.

17. What is 140% of 50?

    70. Calculate $1.40 \times 50 = 70$.

18. Convert 150% to a decimal.

    1.5. Divide percent by 100 to get decimal form.

19. What is 10\% of 500?

    50. Convert 10% to decimal (0.10) and multiply by 500.

20. State the formula for finding $p\%$ of a number $N$.

    $\frac{p}{100}N$. Multiply the number by the decimal equivalent of the percent.

21. What percent of $90$ is $27$?

    $30\%$. $\frac{27}{90} \times 100\% = 30\%$

22. What is $30\%$ of $50$?

    $15$. $0.30 \times 50 = 15$

23. What number is $35\%$ of $200$?

    $70$. $0.35 \times 200 = 70$

24. What is the final price after a $10\%$ tax on $50$?

    $55$. $50 \times 1.10 = 55$

25. How do you express 1.5 as a percent?

    150\%. Move decimal point two places right to convert to percent.

26. A value changes from $30$ to $24$. What is the percent change?

    $-20\%$. $\frac{24-30}{30} \times 100\% = -20\%$

27. Identify the equation to find "$A$ is $p\%$ of what number?"

    $A=\frac{p}{100}x$. Solve for the unknown whole by rearranging the percent equation.

28. What number is $40\%$ of $250$?

    $100$. $0.40 \times 250 = 100$

29. What is the percent change from 60 to 90?

    50%. Increase is $30$, original is $60$: $\frac{30}{60} \times 100 = 50\%$.

30. How do you express 0.75 as a percent?

    75\%. Move decimal point two places right to convert to percent.

31. Express 0.125 as a percent.

    12.5%. Multiply decimal by 100 to convert to percent.

32. A quantity is multiplied by $0.75$. What percent decrease does this represent?

    $25\%$. Multiplier $0.75$ represents $100\% - 25\% = 75\%$ of original.

33. What is the percent increase from 50 to 75?

    50\%. Change is 25, divided by original 50, times 100%.

34. What is the decimal equivalent of $25\%$?

    $0.25$. $25\% = \frac{25}{100} = 0.25$

35. State the equation for "$p\%$ of $N$ is $A$".

    $\frac{p}{100}N=A$. Standard equation format for percent problems.

36. Express 2% as a decimal.

    0.02. Divide percent by 100 to get decimal form.

37. What is the decimal form of $p\%$?

    $\frac{p}{100}$. Divide the percent by $100$ to convert to decimal form.

38. Identify the equation to find what percent $A$ is of $B$.

    $\frac{A}{B}\times 100\%$. Divide the part by the whole and multiply by $100$ for percent.

39. A $60$ item is discounted $30\%$ and then taxed $10\%$. What is the final price?

    $46.2$. $60 \times 0.70 \times 1.10 = 46.2$

40. After a $20\%$ decrease, a value becomes $72$. What was the original value?

    $90$. If $80\%$ of original equals $72$, then original equals $\frac{72}{0.8} = 90$.

41. Convert $\frac{7}{8}$ to a percent.

    87.5%. $\frac{7}{8} = 0.875 = 87.5\%$ when converted.

42. What is the percent increase from 40 to 50?

    25\%. Change is 10, divided by original 40, times 100%.

43. How do you convert 0.03 to a percent?

    3\%. Move decimal point two places right to convert to percent.

44. What is the percent equivalent of $1.2$?

    $120\%$. $1.2 \times 100 = 120\%$

45. Find the percent increase from 50 to 75.

    50\%. Change is $25$, original is $50$: $\frac{25}{50} \times 100 = 50\%$.

46. State the percent change formula from old value $O$ to new value $N$.

    $\frac{N-O}{O}\times 100\%$. Shows difference from old value as a percent of the old value.

47. What is 10% of 1,000?

    100. Calculate $0.10 \times 1000 = 100$.

48. Identify the percent error formula when accepted value is $A$ and experimental value is $E$.

    $\frac{|E-A|}{A}\times 100\%$. Absolute difference divided by accepted value, converted to percent.

49. If 80 is 20% of a number, what is the number?

    400. If $80 = 0.20x$, then $x = 80 \div 0.20 = 400$.

50. What is 15\% of 200?

    30. Convert 15% to decimal (0.15) and multiply by 200.

51. What is $15\%$ of $80$?

    $12$. $0.15 \times 80 = 12$

52. What is 75% of 80?

    60. Calculate $0.75 \times 80 = 60$.

53. What is the percent decrease from 200 to 150?

    25\%. Change is 50, divided by original 200, times 100%.

54. What is the formula for percent increase?

    Percent Increase = $\frac{\text{New} - \text{Original}}{\text{Original}} \times 100$. Subtract original from new, divide by original, multiply by 100.

55. How do you express $\frac{1}{2}$ as a percent?

    50\%. Divide 1 by 2 to get 0.5, then convert to percent.

56. What is the formula for percent decrease?

    Percent Decrease = $\frac{\text{Original} - \text{New}}{\text{Original}} \times 100$. Subtract new from original, divide by original, multiply by 100.

57. How do you express $\frac{3}{4}$ as a percent?

    75\%. Divide 3 by 4 to get 0.75, then convert to percent.

58. What is 0.5% of 200?

    1. Calculate $0.005 \times 200 = 1$.

59. How do you convert 0.15 to a percent?

    15\%. Move decimal point two places right to convert to percent.

60. What is the percent decrease from 80 to 60?

    25\%. Change is 20, divided by original 80, times 100%.

61. What is the original price if a 20% discount gives a sale price of $80$?

    $100$. If $80\%$ of original equals $80$, then original equals $\frac{80}{0.8} = 100$.

62. Convert $\frac{3}{5}$ to a percent.

    60%. $\frac{3}{5} = 0.6 = 60\%$ when converted.

63. What is 50\% of 120?

    60. Convert 50% to decimal (0.50) and multiply by 120.

64. A value increases from $40$ to $50$. What is the percent increase?

    $25\%$. $\frac{50-40}{40} \times 100\% = 25\%$

65. What is $50\%$ of 120?

    60. Convert $50\%$ to decimal ($0.50$) and multiply by $120$.

66. After a $25\%$ increase, a value becomes $100$. What was the original value?

    $80$. If $125\%$ of original equals $100$, then original equals $\frac{100}{1.25} = 80$.

67. What is 25% of 200?

    50. Calculate $0.25 \times 200 = 50$.

68. What is the percent change from $50$ to $65$?

    $30\%$. $\frac{65-50}{50} \times 100\% = 30\%$

69. Convert 0.2 to a percent.

    20%. Multiply decimal by 100 to get percentage.

70. What is the formula for converting a percent to a decimal?

    Decimal = $\frac{\text{Percent}}{100}$. Divide percent by 100 to shift decimal point two places left.

71. What is the formula to convert a fraction to a percent?

    Percent = $\frac{\text{Numerator}}{\text{Denominator}} \times 100\%$. Divide fraction value by 1 and multiply by 100%.

72. What is the formula to convert a decimal to a percent?

    Decimal $\times 100 = \text{Percent}$. Shift decimal point two places right to convert.

73. What is the decimal equivalent of $0.4\%$?

    $0.004$. $0.4\% = \frac{0.4}{100} = 0.004$

74. How do you convert 0.25 to a percent?

    25\%. Move decimal point two places right to convert to percent.

75. What is the percent change from $200$ to $150$?

    $-25\%$. $\frac{150-200}{200} \times 100\% = -25\%$

76. What is 20\% of 150?

    30. Convert 20% to decimal (0.20) and multiply by 150.

77. Convert 3.5 to a percent.

    350%. Multiply decimal by 100 to get percentage.

78. State the multiplier for decreasing a value by $r\%$.

    $1-\frac{r}{100}$. Subtracting from $1$ accounts for the original amount minus the decrease.

79. Identify the formula for simple interest $I$ with principal $P$, rate $r\%$, and time $t$ years.

    $I=P\cdot \frac{r}{100}\cdot t$. Interest equals principal times rate times time.

80. What is the formula for converting a decimal to a percent?

    Percent = Decimal $\times 100\%$. Multiply decimal by 100 to shift decimal point two places right.

81. What is the percent equivalent of $0.07$?

    $7\%$. $0.07 \times 100 = 7\%$

82. What is the formula to find the percent of a number?

    Part = $\frac{\text{Percent}}{100} \times \text{Whole}$. Multiply the decimal form of the percent by the whole number.

83. What is the fraction form of $p\%$ in simplest terms?

    $\frac{p}{100}$ reduced. Convert percent to fraction and simplify by dividing by common factors.

84. What is the formula for calculating a percentage?

    Percentage = $\frac{\text{Part}}{\text{Whole}} \times 100\%$. Standard formula for finding what percent one value is of another.

85. What is the percent change from 80 to 60?

    -25%. Decrease is $20$, original is $80$: $\frac{20}{80} \times 100 = 25\%$ decrease.

86. What is the sale price after a $15\%$ discount on $120$?

    $102$. $120 \times 0.85 = 102$

87. Convert 2.75 to a percent.

    275%. Multiply decimal by 100 to convert to percent.

88. What is $12.5\%$ of $64$?

    $8$. $0.125 \times 64 = 8$

89. A quantity is multiplied by $1.08$. What percent increase does this represent?

    $8\%$. Multiplier $1.08$ represents original value plus $8\%$ increase.

90. Express 0.45 as a percent.

    45%. Multiply decimal by 100 to convert to percent.

91. Convert 0.01 to a percent.

    1%. Multiply decimal by 100 to convert to percent.

92. How do you express 0.6 as a percent?

    60\%. Move decimal point two places right to convert to percent.

93. If $x$ is increased by $10\%$ and then decreased by $10\%$, what is the overall multiplier?

    $0.99$. $1.10 \times 0.90 = 0.99$

94. What is the percent form of a decimal $d$?

    $100d\%$. Multiply the decimal by $100$ to convert to percent form.

95. Express 1.25 as a percent.

    125%. Multiply decimal by 100 to get percentage.

96. How do you convert $0.25$ to a percent?

    $25\%$. Move decimal point two places right to convert to percent.

97. What is the formula to calculate percent change?

    Percent Change = $\frac{\text{New} - \text{Old}}{\text{Old}} \times 100\%$. Standard formula comparing new and old values to find percentage change.

98. How do you convert 45\% to a decimal?

    0.45. Move decimal point two places left to convert percent to decimal.

99. What is the original price if a $20\%$ discount gives a sale price of $80$?

    $100$. If $80\%$ of original equals $80$, then original equals $\frac{80}{0.8} = 100$.

100. Convert $\frac{1}{3}$ to a percent (rounded).

     33.33%. $\frac{1}{3} = 0.3333... = 33.33\%$ when rounded.

101. State the multiplier for increasing a value by $r\%$.

     $1+\frac{r}{100}$. Adding $1$ accounts for the original amount plus the increase.

102. Find the percent decrease from 200 to 150.

     25%. Decrease is $50$, original is $200$: $\frac{50}{200} \times 100 = 25\%$.

103. Find 30% of 250.

     75. Calculate $0.30 \times 250 = 75$.

104. Express 5% as a fraction in simplest form.

     $\frac{1}{20}$. $5\% = \frac{5}{100} = \frac{1}{20}$ in lowest terms.

105. Find the percent increase from 40 to 100.

     150%. Increase is $60$, original is $40$: $\frac{60}{40} \times 100 = 150\%$.

106. How do you convert 2.5 to a percent?

     250\%. Move decimal point two places right to convert to percent.

107. How do you express 1.25 as a percent?

     125\%. Move decimal point two places right to convert to percent.

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