- A9
- B18
- C36
- D
Step-by-Step Solution
Number of pieces = . The trap is multiplying the two lengths instead of dividing, which gives — that is an area-like quantity, not a count.
Answer: B) 18
A rope m long is cut into pieces each m long. How many pieces are obtained?
Class 8Rational NumbersRational Numbers
Key idea: Closure of rationals
Rationals are **closed under addition, subtraction, and multiplication** — the result is always rational.
But **division is closed only if you exclude division by 0**: for any rationals a and b ≠ 0, a ÷ b is rational.
This is more than integers (which weren't closed under division at all) and more than fractions (which sometimes had subtraction lead outside the fractions). Rationals form the smallest 'nice' number system that supports all four basic operations (with the 0-divisor exception).
But **division is closed only if you exclude division by 0**: for any rationals a and b ≠ 0, a ÷ b is rational.
This is more than integers (which weren't closed under division at all) and more than fractions (which sometimes had subtraction lead outside the fractions). Rationals form the smallest 'nice' number system that supports all four basic operations (with the 0-divisor exception).
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More Class 8 Rational Numbers practice
Which expression equals -2/3 × (5/7 - 4/9 ) by the distributive property?The reciprocal of a rational number x is -5/12. What is x?How many rational numbers with denominator 63 lie strictly between 2/7 and 3/7?Between which two consecutive integers does -11/4 lie on the number line?The sum of two rational numbers is -1/3. If one of them is 5/6, find the other.