Missing Sequence Terms - ISEE Middle Level: Quantitative Reasoning
Card 1 of 21
What is the missing term in the arithmetic sequence $4, 7, 10, _, 16$?
What is the missing term in the arithmetic sequence $4, 7, 10, _, 16$?
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$13$. The arithmetic sequence has a common difference of $3$, so the missing term is found by adding $3$ to $10$.
$13$. The arithmetic sequence has a common difference of $3$, so the missing term is found by adding $3$ to $10$.
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What is the missing term in the arithmetic sequence $-3, 1, 5, _, 13$?
What is the missing term in the arithmetic sequence $-3, 1, 5, _, 13$?
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$9$. The arithmetic sequence has a common difference of $4$, so the missing term is found by adding $4$ to $5$.
$9$. The arithmetic sequence has a common difference of $4$, so the missing term is found by adding $4$ to $5$.
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What is the missing term in the arithmetic sequence $20, 15, 10, _, 0$?
What is the missing term in the arithmetic sequence $20, 15, 10, _, 0$?
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$5$. The arithmetic sequence has a common difference of $-5$, so the missing term is found by subtracting $5$ from $10$.
$5$. The arithmetic sequence has a common difference of $-5$, so the missing term is found by subtracting $5$ from $10$.
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What is the missing term in the arithmetic sequence $\frac{1}{2}, 1, \frac{3}{2}, _, \frac{5}{2}$?
What is the missing term in the arithmetic sequence $\frac{1}{2}, 1, \frac{3}{2}, _, \frac{5}{2}$?
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$2$. The arithmetic sequence has a common difference of $\frac{1}{2}$, so the missing term is found by adding $\frac{1}{2}$ to $\frac{3}{2}$.
$2$. The arithmetic sequence has a common difference of $\frac{1}{2}$, so the missing term is found by adding $\frac{1}{2}$ to $\frac{3}{2}$.
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What is the missing term in the geometric sequence $81, 27, 9, _, 1$?
What is the missing term in the geometric sequence $81, 27, 9, _, 1$?
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$3$. The geometric sequence has a common ratio of $\frac{1}{3}$, so the missing term is found by multiplying $9$ by $\frac{1}{3}$.
$3$. The geometric sequence has a common ratio of $\frac{1}{3}$, so the missing term is found by multiplying $9$ by $\frac{1}{3}$.
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What is the missing term in the geometric sequence $\frac{1}{4}, \frac{1}{2}, 1, _, 4$?
What is the missing term in the geometric sequence $\frac{1}{4}, \frac{1}{2}, 1, _, 4$?
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$2$. The geometric sequence has a common ratio of $2$, so the missing term is found by multiplying $1$ by $2$.
$2$. The geometric sequence has a common ratio of $2$, so the missing term is found by multiplying $1$ by $2$.
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What is the missing term in the square-number sequence $1, 4, 9, _, 25$?
What is the missing term in the square-number sequence $1, 4, 9, _, 25$?
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$16$. The sequence consists of squares of consecutive integers from $1^2$ to $5^2$, so the missing term is $4^2$.
$16$. The sequence consists of squares of consecutive integers from $1^2$ to $5^2$, so the missing term is $4^2$.
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What is the missing term in the cube-number sequence $1, 8, 27, _, 125$?
What is the missing term in the cube-number sequence $1, 8, 27, _, 125$?
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$64$. The sequence consists of cubes of consecutive integers from $1^3$ to $5^3$, so the missing term is $4^3$.
$64$. The sequence consists of cubes of consecutive integers from $1^3$ to $5^3$, so the missing term is $4^3$.
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What is the missing term in the triangular-number sequence $1, 3, 6, _, 15$?
What is the missing term in the triangular-number sequence $1, 3, 6, _, 15$?
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$10$. The triangular number sequence is the sum of the first $n$ integers, so the missing term is for $n=4$.
$10$. The triangular number sequence is the sum of the first $n$ integers, so the missing term is for $n=4$.
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What is the missing term in the Fibonacci-type sequence $2, 3, 5, 8, _, 21$?
What is the missing term in the Fibonacci-type sequence $2, 3, 5, 8, _, 21$?
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$13$. In this Fibonacci-type sequence, each term is the sum of the two preceding ones, so add $5$ and $8$.
$13$. In this Fibonacci-type sequence, each term is the sum of the two preceding ones, so add $5$ and $8$.
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What is the missing term in the sequence $1, 3, 6, 10, _, 21$?
What is the missing term in the sequence $1, 3, 6, 10, _, 21$?
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$15$. The triangular number sequence follows $\frac{n(n+1)}{2}$ for $n=1$ to $5$, so the missing term is for $n=5$.
$15$. The triangular number sequence follows $\frac{n(n+1)}{2}$ for $n=1$ to $5$, so the missing term is for $n=5$.
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What is the missing term in the sequence $2, 5, 11, 23, _, 95$?
What is the missing term in the sequence $2, 5, 11, 23, _, 95$?
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$47$. Each term follows the rule of multiplying the previous by $2$ and adding $1$, so apply to $23$.
$47$. Each term follows the rule of multiplying the previous by $2$ and adding $1$, so apply to $23$.
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What is the missing term in the sequence $100, 50, 25, _, 6.25$?
What is the missing term in the sequence $100, 50, 25, _, 6.25$?
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$12.5$. The geometric sequence has a common ratio of $\frac{1}{2}$, so the missing term is found by multiplying $25$ by $\frac{1}{2}$.
$12.5$. The geometric sequence has a common ratio of $\frac{1}{2}$, so the missing term is found by multiplying $25$ by $\frac{1}{2}$.
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What is the missing term in the sequence $1, 2, 4, 7, _, 16$?
What is the missing term in the sequence $1, 2, 4, 7, _, 16$?
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$11$. The differences increase by $1$ each time ($+1, +2, +3, +4$), so add $4$ to $7$.
$11$. The differences increase by $1$ each time ($+1, +2, +3, +4$), so add $4$ to $7$.
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What is the missing term in the alternating sequence $2, 5, 4, 7, 6, _$?
What is the missing term in the alternating sequence $2, 5, 4, 7, 6, _$?
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$9$. The sequence consists of two interleaved arithmetic sequences increasing by $2$, with odd positions starting at $2$ and even at $5$, so the sixth term follows the even sequence.
$9$. The sequence consists of two interleaved arithmetic sequences increasing by $2$, with odd positions starting at $2$ and even at $5$, so the sixth term follows the even sequence.
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What is the missing term in the sequence of powers $2^1, 2^2, 2^3, _, 2^5$?
What is the missing term in the sequence of powers $2^1, 2^2, 2^3, _, 2^5$?
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$2^4$. The sequence is powers of $2$ with consecutive exponents from $1$ to $5$, so the missing term has exponent $4$.
$2^4$. The sequence is powers of $2$ with consecutive exponents from $1$ to $5$, so the missing term has exponent $4$.
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What is the missing term in the sequence $3^0, 3^1, _, 3^3, 3^4$?
What is the missing term in the sequence $3^0, 3^1, _, 3^3, 3^4$?
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$3^2$. The sequence is powers of $3$ with consecutive exponents from $0$ to $4$, so the missing term has exponent $2$.
$3^2$. The sequence is powers of $3$ with consecutive exponents from $0$ to $4$, so the missing term has exponent $2$.
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What is the missing term in the sequence $\frac{1}{3}, \frac{1}{6}, \frac{1}{12}, _, \frac{1}{48}$?
What is the missing term in the sequence $\frac{1}{3}, \frac{1}{6}, \frac{1}{12}, _, \frac{1}{48}$?
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$\frac{1}{24}$. The geometric sequence has a common ratio of $\frac{1}{2}$, so the missing term is found by multiplying $\frac{1}{12}$ by $\frac{1}{2}$.
$\frac{1}{24}$. The geometric sequence has a common ratio of $\frac{1}{2}$, so the missing term is found by multiplying $\frac{1}{12}$ by $\frac{1}{2}$.
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What is the missing term in the sequence $0.2, 0.4, 0.8, _, 3.2$?
What is the missing term in the sequence $0.2, 0.4, 0.8, _, 3.2$?
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$1.6$. The geometric sequence has a common ratio of $2$, so the missing term is found by multiplying $0.8$ by $2$.
$1.6$. The geometric sequence has a common ratio of $2$, so the missing term is found by multiplying $0.8$ by $2$.
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What is the missing term in the sequence $1, 4, 2, 8, 4, _$?
What is the missing term in the sequence $1, 4, 2, 8, 4, _$?
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$16$. The sequence alternates between multiplying by $4$ and dividing by $2$, so multiply $4$ by $4$.
$16$. The sequence alternates between multiplying by $4$ and dividing by $2$, so multiply $4$ by $4$.
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What is the missing term in the geometric sequence $3, 6, 12, _, 48$?
What is the missing term in the geometric sequence $3, 6, 12, _, 48$?
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$24$. The geometric sequence has a common ratio of $2$, so the missing term is found by multiplying $12$ by $2$.
$24$. The geometric sequence has a common ratio of $2$, so the missing term is found by multiplying $12$ by $2$.
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