Quantitative Aptitude · Mathematics
Number and Polynomial Division
133 Questions
Number and polynomial division tests your skill in finding quotients, remainders, and applying theorems to algebraic expressions. These calculations are a staple in quantitative aptitude exams. Solving these problems enhances speed and accuracy for competitive tests.
Number remaindersPolynomial divisionQuotient and remainderFactor and remainder theoremSuccessive division
Number and Polynomial Division Questions
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1 or 3
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1 or 5
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3 or 5
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4 or 5
A
Correct answer
Explanation
Using the sum of cubes formula or modular arithmetic: 16^3 + 17^3 + 18^3 + 19^3. 16+19=35 and 17+18=35. Since a^3+b^3 is divisible by a+b, the sum is divisible by 35. Also, the sum of four consecutive cubes is divisible by 4. Thus it is divisible by 70, leaving remainder 0.
B
Correct answer
Explanation
Let the number be N. When divided by 36, remainder is 19, so N = 36k + 19 for some integer k. N = 36k + 19 = 12(3k) + 12 + 7 = 12(3k+1) + 7. When N is divided by 12, the remainder is 7. (192 would mean N > 36, which is incorrect for a remainder).
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(n^2)-2
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(n^2)-3
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(n-2)^2
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(n-3)^2
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(n-4)^2
D
Correct answer
Explanation
If n divided by 7 leaves remainder 3, then n = 7k + 3. Then (n-3) = 7k. Squaring both sides gives (n-3)^2 = (7k)^2 = 49k^2. Since 49k^2 is a multiple of 49, (n-3)^2 is exactly divisible by 49.
B
Correct answer
Explanation
A number's remainder when divided by 9 is the same as the remainder of the sum of its digits divided by 9. The sum of 7+6+5+4+3+2+9+8+7+6+5+4+3+2+1+8 is 80. 80 divided by 9 is 8 with a remainder of 8.
A
Correct answer
Explanation
Using Fermat's Little Theorem: for prime p=101, a^100 ≡ 1 (mod 101) when a is not divisible by 101. Therefore, 205^205 ≡ 205^(2×100 + 5) ≡ (205^100)^2 × 205^5 ≡ 1^2 × 205^5. Simplify: 205 ≡ 3 (mod 101), so 3^5 = 243 ≡ 41 (mod 101). The remainder is 41.
C
Correct answer
Explanation
Since a > b, a! = a * (a-1) * ... * (b+1) * b!. Therefore, a! is a multiple of b!, and the remainder of any multiple divided by its factor is always 0.
D
Correct answer
Explanation
The number 11 satisfies all conditions: 11/2 leaves remainder 1, 11/3 leaves remainder 2, and 11/4 leaves remainder 3. It is the smallest such positive integer.
C
Correct answer
Explanation
Let the number be $10x + y$. From the first condition, $10x + y = 4(x + y) + 3$, which simplifies to $2x - y = 1$. From the second, $10x + y = 3xy + 5$. Substituting $y = 2x - 1$ into the second equation gives $10x + 2x - 1 = 3x(2x - 1) + 5$, leading to $6x^2 - 15x + 6 = 0$. Solving gives $x=2$, so $y=3$. The number is 23.
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3
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3^17
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394
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No Such Interger
A
Correct answer
Explanation
If a number leaves remainder 3 when divided by 17 and 23, then that number minus 3 is divisible by both 17 and 23. Since 3 itself satisfies this condition (3-3=0, which is divisible by any number), 3 is the least positive integer with this property. The LCM of 17 and 23 is 391, so other solutions are 394, 785, etc.
D
Correct answer
Explanation
We need 7^2001 mod 14. Note that 7 mod 14 = 7, and 7² = 49, which gives 49 mod 14 = 7 (since 49 = 3×14 + 7). Similarly, 7³ mod 14 = 7² × 7 mod 14 = 7 × 7 mod 14 = 7. By induction, all positive powers of 7 give remainder 7 when divided by 14. Therefore, 7^2001 mod 14 = 7. Option D is correct. Option A would be true if dividing by 6, and Option B incorrectly assumes divisibility.
D
Correct answer
Explanation
(3264) in base 7 is 3(7^3) + 2(7^2) + 6(7^1) + 4(7^0) = 1029 + 98 + 42 + 4 = 1173 in base 10. 1173 divided by 8 is 146 with a remainder of 5. The other options are incorrect remainders.
A
Correct answer
Explanation
Using the division algorithm: Dividend = Divisor × Quotient + Remainde r. Here: 4150 = Divisor × 55 + 25. So 4150 - 25 = 4125 = Divisor × 55. Therefore: Divisor = 4125 ÷ 55 = 75.
B
Correct answer
Explanation
When a number is divided by 36 and leaves remainder 19, we can write: Number = 36k + 19 for some integer k. Since 36 = 12 × 3, when we divide by 12, we get: Number = 12(3k) + 12 + 7 = 12(3k+1) + 7. Thus the remainder is 7. Option C (192) is incorrect as it's greater than the divisor 12.