Answer:
He used 55% protein 500 pounds and 25% protein 1000 pounds
Step-by-step explanation:
x pounds of 55% contains x * 0.55 pounds of pure protein
y pounds of 25% contains x * 0.25 pounds of pure protein
1500 pounds of 35% contains 1500 * 0.35 = 525 pounds of pure protein
x + y = 1500 ... (1)
0.55 x + 0.25 y = 525 ...(2)
0.25 times both sides of (1)
0.25 x + 0.25 y = 1500 * 0.25 = 375 ... (3)
(2) - (3) 0.3 x = 150 .... divide 0.3 on both sides
x = 500
y = 1500 - 500 = 1000
