A car mechanic has a tin containing 5 litres of engine oil - OCR - GCSE Maths - Question 3 - 2021 - Paper 1
Question 3
A car mechanic has a tin containing 5 litres of engine oil.
Each week they use 450 millilitres of this oil for their vehicles.
The car mechanic says
After 9 weeks I... show full transcript
Worked Solution & Example Answer:A car mechanic has a tin containing 5 litres of engine oil - OCR - GCSE Maths - Question 3 - 2021 - Paper 1
Step 1
Calculate the Total Oil Used After 9 Weeks
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 find out how much oil is used after 9 weeks, calculate:
Total Oil Used = Weekly Usage × Number of Weeks
Substituting the values:
Total Oil Used = 450 ext{ ml} imes 9 = 4050 ext{ ml}
Step 2
Convert Litres to Millilitres
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
Since 1 litre is equal to 1000 millilitres, convert 5 litres to millilitres:
5 litres = 5 imes 1000 = 5000 ext{ ml}
Step 3
Calculate 80% of the Total Oil
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Sign up now to view full answer, or log in if you already have an account!
Answer
Now we compare the total oil used after 9 weeks (4050 ml) with 80% of the total oil (4000 ml). Since 4050 ml is greater than 4000 ml, the mechanic's statement is incorrect. After 9 weeks, they will have used more than 80% of the oil.
