white paint and red paint are mixed in the ratio of 2 : 3 to make 15 litres.
How much more red paint needs to be added so that the ratio of white to red paint becomes 1 : 5?
Thanks
3 /[2+3] x 15 = 9 Liters of red paint
2 /[2+3] x 15 =6 Liters of white paint
6 / [9 +R] = 1/5
R = 21 Liters of red paint must be added to get a ratio of 1 : 5, or:
6 : [9 + 21] = 6 : 30 = 1 : 5
+168 
