Edexcel GCSE Maths: Ratio, Proportion and Rates of Change

Asha, Ben and Carl share some money in the ratio $4 : 5 : 7$4:5:7.

Carl receives £36 more than Asha.

(a) Work out the total amount of money shared. (3 marks)

(b) Ben gives $20\%$20% of his share to a charity. Work out how much Ben gives to the charity. (2 marks)

$y$y is inversely proportional to the square of $x$x.

When $x = 4$x=4, $y = 5$y=5.

(a) Find a formula for $y$y in terms of $x$x. (3 marks)

(b) Find the value of $y$y when $x = 10$x=10. (1 mark)

A solid metal block is in the shape of a cuboid. The block has volume $250\ \text{cm}^3$250 cm3 and mass $1925\ \text{g}$1925 g.

(a) Work out the density of the metal, giving your answer in $\text{g/cm}^3$g/cm3. (2 marks)

(b) A different block is made of the same metal and has mass $3080\ \text{g}$3080 g. Work out the volume of this block. (2 marks)

The value of a car was £18 000 when it was new. Each year the value of the car decreases by $15\%$15% of its value at the start of that year.

Work out the value of the car after 3 years. (3 marks)

Shop A sells a 750 g jar of honey for £4.50. Shop B sells a 1.2 kg jar of the same honey for £6.96.

Show which shop offers the better value for money. You must show your working. (2 marks)

A train travels $150$150 km in $1$1 hour $30$30 minutes.

Work out the average speed of the train in km/h. (1 mark)