Question 4
Fractions, Decimals and ApproximationSimplify, correct to three significant figures, (27.63)2 − (12.37)2.
- A.614
- B.612
- C.611
- D.610
Show the answer and explanation
Answer: D (610)
Explanation
Use the difference of two squares: (27.63 + 12.37)(27.63 − 12.37) = 40 × 15.26 = 610.4, which is 610 to 3 s.f.