Answer:
The soda costs 2.20 and the sandwich costs 7.70
Step-by-step explanation:
To find this, set the soda cost as x. We now know that the sandwich cost is 3.5x. Add these together and set equal to 9.90
x + 3.5x = 9.90
4.5x = 9.90
x = 2.20
This is the cost of the soda. Now we can multiply that by 3.5 to get the sandwich cost.
3.5 * 2.20 = 7.70
The 4 litres of red has to be 2 parts of the mixture, so each part will be 2 litres. Therefore 3 parts of cream will be 6 litres and the one part of blue will be 2 litres.
