Question 1030784
- How many grams of cream containing 12%: Let the amount be x
- added to 1500 containing 2%: this will be 1500-x
-  to obtain 1500 at 4%: this will be 0.04(1500)
We have so far: 
0.12x+0.02(1500-x) = 0.04(1500)
0.12x+30-0.02x = 60
0.10x = 30
x = 300 You have to add 300 grams of 12%