Missing Sequence Terms - ISEE Lower Level: Quantitative Reasoning
Card 1 of 22
What is the missing term in the sequence $2, 4, 7, 11, _, 22$ if the differences are $+2, +3, +4, \dots$?
What is the missing term in the sequence $2, 4, 7, 11, _, 22$ if the differences are $+2, +3, +4, \dots$?
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$16$. The differences increase by $1$ each time starting from $+2$, so the term after $11$ is $11 + 5 = 16$.
$16$. The differences increase by $1$ each time starting from $+2$, so the term after $11$ is $11 + 5 = 16$.
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What is the missing term in the sequence $9, 6, 8, 5, 7, _, 6$ (alternating $-3, +2$)?
What is the missing term in the sequence $9, 6, 8, 5, 7, _, 6$ (alternating $-3, +2$)?
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$4$. The sequence alternates between subtracting $3$ and adding $2$, so the term after $7$ is $7 - 3 = 4$.
$4$. The sequence alternates between subtracting $3$ and adding $2$, so the term after $7$ is $7 - 3 = 4$.
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What is the missing term in the sequence $5, 6, 8, 11, _, 20$ if the differences are $+1, +2, +3, \dots$?
What is the missing term in the sequence $5, 6, 8, 11, _, 20$ if the differences are $+1, +2, +3, \dots$?
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$15$. The differences increase by $1$ each time starting from $+1$, so the term after $11$ is $11 + 4 = 15$.
$15$. The differences increase by $1$ each time starting from $+1$, so the term after $11$ is $11 + 4 = 15$.
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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 sequence is geometric with a common ratio of $\frac{1}{3}$, so the term after $9$ is $9 \times \frac{1}{3} = 3$.
$3$. The sequence is geometric with a common ratio of $\frac{1}{3}$, so the term after $9$ is $9 \times \frac{1}{3} = 3$.
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What is the missing term in the geometric sequence $2, 6, 18, _, 162$?
What is the missing term in the geometric sequence $2, 6, 18, _, 162$?
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$54$. The sequence is geometric with a common ratio of $3$, so the term after $18$ is $18 \times 3 = 54$.
$54$. The sequence is geometric with a common ratio of $3$, so the term after $18$ is $18 \times 3 = 54$.
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What is the missing term in the arithmetic sequence $12, 9, 6, _, 0$?
What is the missing term in the arithmetic sequence $12, 9, 6, _, 0$?
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$3$. The sequence is arithmetic with a common difference of $-3$, so the term after $6$ is $6 - 3 = 3$.
$3$. The sequence is arithmetic with a common difference of $-3$, so the term after $6$ is $6 - 3 = 3$.
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What is the missing term in the arithmetic sequence $3, _, 13, 18, 23$?
What is the missing term in the arithmetic sequence $3, _, 13, 18, 23$?
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$8$. The sequence is arithmetic with a common difference of $5$, so the term after $3$ is $3 + 5 = 8$.
$8$. The sequence is arithmetic with a common difference of $5$, so the term after $3$ is $3 + 5 = 8$.
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What is the missing term in the arithmetic sequence $-4, -1, 2, _, 8$?
What is the missing term in the arithmetic sequence $-4, -1, 2, _, 8$?
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$5$. The sequence is arithmetic with a common difference of $3$, so the term after $2$ is $2 + 3 = 5$.
$5$. The sequence is arithmetic with a common difference of $3$, so the term after $2$ is $2 + 3 = 5$.
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What is the missing term in the arithmetic sequence $7, 11, 15, _, 23$?
What is the missing term in the arithmetic sequence $7, 11, 15, _, 23$?
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$19$. The sequence is arithmetic with a common difference of $4$, so the term after $15$ is $15 + 4 = 19$.
$19$. The sequence is arithmetic with a common difference of $4$, so the term after $15$ is $15 + 4 = 19$.
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What is the missing term in the geometric sequence $\frac{1}{2}, 1, 2, _, 8$?
What is the missing term in the geometric sequence $\frac{1}{2}, 1, 2, _, 8$?
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$4$. The sequence is geometric with a common ratio of $2$, so the term after $2$ is $2 \times 2 = 4$.
$4$. The sequence is geometric with a common ratio of $2$, so the term after $2$ is $2 \times 2 = 4$.
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What is the missing term in the geometric sequence $5, _, 45, 135$?
What is the missing term in the geometric sequence $5, _, 45, 135$?
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$15$. The sequence is geometric with a common ratio of $3$, so the term after $5$ is $5 \times 3 = 15$.
$15$. The sequence is geometric with a common ratio of $3$, so the term after $5$ is $5 \times 3 = 15$.
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What is the missing term in the sequence of perfect squares $1, 4, _, 16, 25$?
What is the missing term in the sequence of perfect squares $1, 4, _, 16, 25$?
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$9$. The sequence consists of perfect squares, so the term after $4$ is $3^2 = 9$.
$9$. The sequence consists of perfect squares, so the term after $4$ is $3^2 = 9$.
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What is the missing term in the sequence of perfect cubes $1, 8, _, 64, 125$?
What is the missing term in the sequence of perfect cubes $1, 8, _, 64, 125$?
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$27$. The sequence consists of perfect cubes, so the term after $8$ is $3^3 = 27$.
$27$. The sequence consists of perfect cubes, so the term after $8$ is $3^3 = 27$.
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What is the missing term in the Fibonacci-type sequence $1, 1, 2, 3, _, 8$?
What is the missing term in the Fibonacci-type sequence $1, 1, 2, 3, _, 8$?
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$5$. The sequence follows the Fibonacci rule where each term is the sum of the two preceding ones, so the term after $3$ is $2 + 3 = 5$.
$5$. The sequence follows the Fibonacci rule where each term is the sum of the two preceding ones, so the term after $3$ is $2 + 3 = 5$.
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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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$13$. The sequence follows the Fibonacci rule where each term is the sum of the two preceding ones, so the term after $8$ is $5 + 8 = 13$.
$13$. The sequence follows the Fibonacci rule where each term is the sum of the two preceding ones, so the term after $8$ is $5 + 8 = 13$.
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What is the missing term in the sequence $2, 5, 10, 17, _, 37$ if the rule is $+3, +5, +7, \dots$?
What is the missing term in the sequence $2, 5, 10, 17, _, 37$ if the rule is $+3, +5, +7, \dots$?
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$26$. The differences increase by $2$ each time starting from $+3$, so the term after $17$ is $17 + 9 = 26$.
$26$. The differences increase by $2$ each time starting from $+3$, so the term after $17$ is $17 + 9 = 26$.
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What is the missing term in $1, 2, 4, 7, 11, _$ if the differences increase by $1$ each time?
What is the missing term in $1, 2, 4, 7, 11, _$ if the differences increase by $1$ each time?
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$16$. The differences increase by $1$ each time starting from $+1$, so the term after $11$ is $11 + 5 = 16$.
$16$. The differences increase by $1$ each time starting from $+1$, so the term after $11$ is $11 + 5 = 16$.
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What is the missing term in the sequence $3, 6, 12, 24, _$?
What is the missing term in the sequence $3, 6, 12, 24, _$?
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$48$. The sequence is geometric with a common ratio of $2$, so the term after $24$ is $24 \times 2 = 48$.
$48$. The sequence is geometric with a common ratio of $2$, so the term after $24$ is $24 \times 2 = 48$.
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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 sequence is geometric with a common ratio of $\frac{1}{2}$, so the term after $25$ is $25 \times \frac{1}{2} = 12.5$.
$12.5$. The sequence is geometric with a common ratio of $\frac{1}{2}$, so the term after $25$ is $25 \times \frac{1}{2} = 12.5$.
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What is the missing term in the sequence $4, 9, 14, _, 24$?
What is the missing term in the sequence $4, 9, 14, _, 24$?
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$19$. The sequence is arithmetic with a common difference of $5$, so the term after $14$ is $14 + 5 = 19$.
$19$. The sequence is arithmetic with a common difference of $5$, so the term after $14$ is $14 + 5 = 19$.
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What is the missing term in the sequence $-2, 1, 4, _, 10$?
What is the missing term in the sequence $-2, 1, 4, _, 10$?
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$7$. The sequence is arithmetic with a common difference of $3$, so the term after $4$ is $4 + 3 = 7$.
$7$. The sequence is arithmetic with a common difference of $3$, so the term after $4$ is $4 + 3 = 7$.
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What is the missing term in the sequence $1, 3, 6, 10, _, 21$ (triangular numbers)?
What is the missing term in the sequence $1, 3, 6, 10, _, 21$ (triangular numbers)?
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$15$. The sequence consists of triangular numbers where each term adds the next integer, so the term after $10$ is $10 + 5 = 15$.
$15$. The sequence consists of triangular numbers where each term adds the next integer, so the term after $10$ is $10 + 5 = 15$.
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