6.4 * 1.25 = (?)3
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Answer: C. 2
Explanation
Multiplying six point four by one point twenty-five yields an exact product value of eight. The equation states this product equals an unknown number raised to the third power. Taking the cube root of eight determines that the unknown number is equal to two. Multiplication of decimals requires careful alignment of decimal places to ensure calculation accuracy. Cube roots find the base number that, when multiplied by itself three times, produces the target value. Basic exponential equations can be solved by recognizing standard powers of small integers.
Decimal arithmetic and exponential calculations appear frequently in scientific and financial data analysis. Engineers use cube roots when calculating volumetric dimensions from scaled physical capacity measurements. Quick mental calculation of small powers improves performance in timed quantitative reasoning tests. Option A suggests one, but one cubed equals one rather than the required product of eight. Option B suggests four, but four cubed equals sixty-four, which is far too large. Option D suggests three, but three cubed equals twenty-seven, exceeding the product value.
- Subject
- Mathematics
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- Mathematics
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- medium
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