There are a total of 45 boys and girls in the school swimming club.
18 of the team are boys and 27 are girls.
The mean age of the 18 boys is 16.2 years.
The mean age of the 27 girls is 16.7 years.
Can you calculate the mean age of all 45 boys and girls?
Answer:
Total age of 18 boys = 16.2 x 18 = 291.60 years
Total age of 27 girls = 16.7 x 27 = 450.90 years
So:
Average (mean) age of 45 children = (291.60 + 450.90)/ 45 = 16.5 years
Week 247 (13 May 2022)
Ahmed has conducted a survey as part of his coursework.
He asked 240 students if they thought Friday 13th was bad luck.
15% of the students said they thought it was bad luck.
3/4 of the students said that they didn’t think it was bad luck.
The rest of the students surveyed didn’t have an opinion.
Can you work out the number of students that didn’t have an opinion.
Answer:
100% – (15% + 3/4 x 100%) = 100 – 90 = 10%
10% of 240 = 24 students