Missing Terms in Sequences - ISEE Middle Level: Mathematics Achievement
Card 1 of 22
What is the missing term in the arithmetic sequence $-4, -1, _, 5, 8$?
What is the missing term in the arithmetic sequence $-4, -1, _, 5, 8$?
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$2$. The arithmetic sequence has a common difference of $3$, so add $3$ to $-1$ to find the missing term.
$2$. The arithmetic sequence has a common difference of $3$, so add $3$ to $-1$ to find the missing term.
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What is the missing term in the arithmetic sequence $3, 7, _, 15, 19$?
What is the missing term in the arithmetic sequence $3, 7, _, 15, 19$?
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$11$. The arithmetic sequence has a common difference of $4$, so add $4$ to $7$ to find the missing term.
$11$. The arithmetic sequence has a common difference of $4$, so add $4$ to $7$ to find the missing term.
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What is the missing term in the alternating sequence $10, 7, 14, 11, _, 15$?
What is the missing term in the alternating sequence $10, 7, 14, 11, _, 15$?
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$18$. The alternating sequence interweaves two arithmetic progressions with common difference $4$, placing $18$ in the fifth position.
$18$. The alternating sequence interweaves two arithmetic progressions with common difference $4$, placing $18$ in the fifth position.
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What is the missing term in the sequence $2, 5, 10, 17, _, 37$ (add consecutive odd numbers)?
What is the missing term in the sequence $2, 5, 10, 17, _, 37$ (add consecutive odd numbers)?
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$26$. The sequence adds consecutive odd numbers starting from $3$, so add $9$ to $17$ to find the missing term.
$26$. The sequence adds consecutive odd numbers starting from $3$, so add $9$ to $17$ to find the missing term.
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What is the missing term in the sequence $3, 6, 12, 24, _, 96$ (each term doubles)?
What is the missing term in the sequence $3, 6, 12, 24, _, 96$ (each term doubles)?
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$48$. Each term doubles the previous, so multiply $24$ by $2$ to find the missing term.
$48$. Each term doubles the previous, so multiply $24$ by $2$ to find the missing term.
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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, so add $5$ to $10$ to find the missing term.
$15$. The sequence consists of triangular numbers, so add $5$ to $10$ to find the missing term.
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What is the missing term in the sequence $1, 8, 27, _, 125$ (perfect cubes)?
What is the missing term in the sequence $1, 8, 27, _, 125$ (perfect cubes)?
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$64$. The sequence consists of consecutive perfect cubes, so the fourth term is $4^3$.
$64$. The sequence consists of consecutive perfect cubes, so the fourth term is $4^3$.
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What is the missing term in the sequence $1, 4, 9, _, 25$ (perfect squares)?
What is the missing term in the sequence $1, 4, 9, _, 25$ (perfect squares)?
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$16$. The sequence consists of consecutive perfect squares, so the fourth term is $4^2$.
$16$. The sequence consists of consecutive perfect squares, so the fourth term is $4^2$.
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What is the missing term in the sequence $2, 6, 12, 20, _, 42$ (pronic numbers $n(n+1)$)?
What is the missing term in the sequence $2, 6, 12, 20, _, 42$ (pronic numbers $n(n+1)$)?
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$30$. The sequence consists of pronic numbers $n(n+1)$, so for $n=5$ the term is $5 \times 6$.
$30$. The sequence consists of pronic numbers $n(n+1)$, so for $n=5$ the term is $5 \times 6$.
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What is the missing term in the sequence $1, 11, 21, _, 41$ (numbers ending in $1$ with step $10$)?
What is the missing term in the sequence $1, 11, 21, _, 41$ (numbers ending in $1$ with step $10$)?
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$31$. The arithmetic sequence has a common difference of $10$, so add $10$ to $21$ to find the missing term.
$31$. The arithmetic sequence has a common difference of $10$, so add $10$ to $21$ to find the missing term.
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What is the missing term in the sequence $4, 9, 16, _, 36$ (squares starting at $2^2$)?
What is the missing term in the sequence $4, 9, 16, _, 36$ (squares starting at $2^2$)?
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$25$. The sequence consists of squares of consecutive integers starting from $2$, so the fourth term is $5^2$.
$25$. The sequence consists of squares of consecutive integers starting from $2$, so the fourth term is $5^2$.
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What is the missing term in the geometric sequence $2, 6, _, 54$?
What is the missing term in the geometric sequence $2, 6, _, 54$?
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$18$. The geometric sequence has a common ratio of $3$, so multiply $6$ by $3$ to find the missing term.
$18$. The geometric sequence has a common ratio of $3$, so multiply $6$ by $3$ to find the missing term.
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What is the missing term in the geometric sequence $81, 27, _, 3$?
What is the missing term in the geometric sequence $81, 27, _, 3$?
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$9$. The geometric sequence has a common ratio of $\frac{1}{3}$, so multiply $27$ by $\frac{1}{3}$ to find the missing term.
$9$. The geometric sequence has a common ratio of $\frac{1}{3}$, so multiply $27$ by $\frac{1}{3}$ to find the missing term.
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What is the missing term in the sequence $2, 3, 5, 8, _, 21$ (each term is sum of previous two)?
What is the missing term in the sequence $2, 3, 5, 8, _, 21$ (each term is sum of previous two)?
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$13$. Each term is the sum of the two preceding terms, so add $5$ and $8$ to find the missing term.
$13$. Each term is the sum of the two preceding terms, so add $5$ and $8$ to find the missing term.
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What is the missing term in the sequence $100, 50, 25, _, 6.25$ (each term halves)?
What is the missing term in the sequence $100, 50, 25, _, 6.25$ (each term halves)?
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$12.5$. Each term is half the previous, so divide $25$ by $2$ to find the missing term.
$12.5$. Each term is half the previous, so divide $25$ by $2$ to find the missing term.
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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 geometric sequence has a common ratio of $3$, so multiply $5$ by $3$ to find the missing term.
$15$. The geometric sequence has a common ratio of $3$, so multiply $5$ by $3$ to find the missing term.
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What is the missing term in the geometric sequence $\frac{1}{4}, _, 1, 2$?
What is the missing term in the geometric sequence $\frac{1}{4}, _, 1, 2$?
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$\frac{1}{2}$. The geometric sequence has a common ratio of $2$, so multiply $\frac{1}{4}$ by $2$ to find the missing term.
$\frac{1}{2}$. The geometric sequence has a common ratio of $2$, so multiply $\frac{1}{4}$ by $2$ to find the missing term.
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What is the missing term in the arithmetic sequence $20, 16, 12, _, 4$?
What is the missing term in the arithmetic sequence $20, 16, 12, _, 4$?
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$8$. The arithmetic sequence has a common difference of $-4$, so subtract $4$ from $12$ to find the missing term.
$8$. The arithmetic sequence has a common difference of $-4$, so subtract $4$ from $12$ to find the missing term.
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What is the missing term in the arithmetic sequence $\frac{1}{2}, 1, _, 2$?
What is the missing term in the arithmetic sequence $\frac{1}{2}, 1, _, 2$?
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$\frac{3}{2}$. The arithmetic sequence has a common difference of $\frac{1}{2}$, so add $\frac{1}{2}$ to $1$ to find the missing term.
$\frac{3}{2}$. The arithmetic sequence has a common difference of $\frac{1}{2}$, so add $\frac{1}{2}$ to $1$ to find the missing term.
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What is the missing term in the sequence $1, 2, 4, 7, _, 16$ (add $1,2,3,\dots$)?
What is the missing term in the sequence $1, 2, 4, 7, _, 16$ (add $1,2,3,\dots$)?
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$11$. The sequence adds consecutive integers starting from $1$, so add $4$ to $7$ to find the missing term.
$11$. The sequence adds consecutive integers starting from $1$, so add $4$ to $7$ to find the missing term.
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What is the missing term in the arithmetic sequence $0.3, 0.6, _, 1.2$?
What is the missing term in the arithmetic sequence $0.3, 0.6, _, 1.2$?
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$0.9$. The arithmetic sequence has a common difference of $0.3$, so add $0.3$ to $0.6$ to find the missing term.
$0.9$. The arithmetic sequence has a common difference of $0.3$, so add $0.3$ to $0.6$ to find the missing term.
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What is the missing term in the alternating sequence $1, -2, 3, -4, _, -6$?
What is the missing term in the alternating sequence $1, -2, 3, -4, _, -6$?
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$5$. The sequence alternates positive and negative signs with consecutive integers, so the fifth term is positive $5$.
$5$. The sequence alternates positive and negative signs with consecutive integers, so the fifth term is positive $5$.
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