10 girls and 15 boys sit a test. The mean mark for the boys is 70. The mean mark for girls is 82. Work out the mean mark for the whole class.
boys' total = 70 x 15 = 1050 girls' total = 82 x 10 = 820 Total = 1870 mean = 1870/ 25 = 74.3
SC
Related Maths GCSE answers
All answers ▸A cylinder has radius 2cm and height 9cm. A cone has radius r cm and height h cm. The ratio r : h is 1 : 4. The volume of the cone is equal to the volume of the cylinder. Work out the value of r.
Expand and simplify (6x + 10)(3x - 2)
Tom tosses a coin. Every toss lands on either heads or tails. The coin lands on heads two thirds of the first 24 games. The coin then lands on heads the next 6 games. For all 30 tosses, work out the ratio heads:tails. Give the answer in the simplest form.
You have a list of numbers: 1, 45, 81, 40, 7, 8, 14, 23, 7, 4. Calculate the mode, median, and mean.