Notice that 27 is the cube of 3 (3×3×3 = 27). The same rule should apply to the second pair, so we need a number whose cube is 125. Since 5×5×5 = 125, the missing number is 5, option (2).
PRO TIP
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Related Questions
Choose the correct meaning of the idiom "नौ दो ग्यारह होना".
Assertion (A): Eating citrus fruits such as lemon and orange helps prevent scurvy.
Reason (R): Citrus fruits are rich in Vitamin C.
Choose the correct option.