to make 20 litres of paints you need 6tins of red paints an 9tins of yellow paints. How much yellow paints to use if 3 1/2 tins of red used. How many tins of red an yellow to make 46 litres

Question

show me the way

Answer 1

If 6 tins of red require 9 of yellow then 3½ tins of red require 3½/6 * 9=7*9/12=7*3/4=5¼ tins of yellow. The ratio 6:9 is the same as 3½:5¼ (=14:21 or 2:3, which is the same as 6:9).

If 15 tins of red and yellow make 20 litres, then 20/15=4/3 is the amount of paint in litres in one tin.

46 litres represents 2+3=5 amounts of paint so 2/5 will be red and 3/5 yellow, 2/5*46=18.4 litres of red and 27.6 of yellow. But a tin is 4/3 litres so this is 3/4*18.4=13.8 tins of red and 20.7 of yellow.