8 (a) Work out an estimate for the value of $\sqrt{63.5 \times 101.7}$ - Edexcel - GCSE Maths - Question 9 - 2019 - Paper 1
Question 9
8 (a) Work out an estimate for the value of $\sqrt{63.5 \times 101.7}$.
(2.3)^3 = 148 correct to 3 significant figures.
(b) Find the value of (0.23)^3 correct t... show full transcript
Worked Solution & Example Answer:8 (a) Work out an estimate for the value of $\sqrt{63.5 \times 101.7}$ - Edexcel - GCSE Maths - Question 9 - 2019 - Paper 1
Step 1
Work out an estimate for the value of $\sqrt{63.5 \times 101.7}$
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To estimate 63.5×101.7, we can round 63.5 to 64 and 101.7 to 100. Thus, we calculate:
64×100=6400=80.
So, the estimated value is 80.
Step 2
(2.3)^3 = 148 correct to 3 significant figures.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Calculating 2.33:
2.33=2.3×2.3×2.3=12.167.
Rounding 12.167 to three significant figures gives us 12.2.
Step 3
Find the value of (0.23)^3 correct to 3 significant figures.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Calculating (0.23)3:
(0.23)3=0.23×0.23×0.23=0.012167.
Rounding 0.012167 to three significant figures gives us 0.0122.
Step 4
Find the value of $5^2$.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!