iGCSE Mathematics (0580) - C1.14 Using a calculator - Exam Style Questions Paper 3- New Syllabus
▶️ Answer/Explanation
(a)
First, work out the numerical value inside the fraction numerator: $8.4^2 + 9.3 = 70.56 + 9.3 = 79.86$.
Then, perform the division step: $\frac{79.86}{26.5} \approx 3.01358$.
Taking the square root of this gives the final decimal value: $\sqrt{3.01358} \approx 1.74$.
✅ Answer: 1.74 (or 1.735 to 1.736)
(b)
A negative power represents the reciprocal of that base number raised to a positive power: $4^{-3} = \frac{1}{4^3}$.
Evaluating the denominator exponent gives: $\frac{1}{64}$, which can also be written in its decimal form as $0.015625$.
✅ Answer: 0.015625 (or $\frac{1}{64}$)