Find the square root of 15625.
A125
B145
C150
D135
Answer & Solution
Correct answer: A. 125
1. Estimate: 120² = 14400 and 130² = 16900, so the root is between 120 and 130.
2. The number ends in 5, so its root ends in 5.
3. 125² = 15625, hence the square root is 125.
_Source: RRB Group D CEN-02/2018 PYQ, Q.23._
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