Answer:
[tex]x = 28[/tex] ----- Banana
[tex]y = 54[/tex] ----- Almonds
[tex]z = 18[/tex] ---- Chocolate
Step-by-step explanation:
Let
[tex]x \to[/tex] banana
[tex]y \to[/tex] almonds
[tex]z \to[/tex] chocolate
So, we have:
[tex]x + y + z = 100[/tex] --- total used
[tex]4x + 8y + 6z = 652[/tex] -- i.e. 6.52 * 100 --- total sales from 100 pounds
[tex]y = 3z[/tex]
Required
The number of pounds of each (i.e. x, y and z)
Substitute [tex]y = 3z[/tex] in [tex]x + y + z = 100[/tex]
[tex]x + 3z + z = 100[/tex]
[tex]x + 4z = 100[/tex]
Make x the subject
[tex]x = 100 - 4z[/tex]
Substitute [tex]y = 3z[/tex] in [tex]4x + 8y + 6z = 652[/tex]
[tex]4x + 8 * 3z + 6z = 652[/tex]
[tex]4x + 24z + 6z = 652[/tex]
[tex]4x + 30z = 652[/tex]
Substitute [tex]x = 100 - 4z[/tex]
[tex]4(100 - 4z) + 30z = 652[/tex]
[tex]400 - 16z + 30z = 652[/tex]
Collect like terms
[tex]- 16z + 30z = 652-400[/tex]
[tex]14z = 252[/tex]
Divide by 14
[tex]z = 18[/tex]
Substitute [tex]z = 18[/tex] in [tex]x = 100 - 4z[/tex]
[tex]x = 100 - 4 * 18[/tex]
[tex]x = 100 - 72[/tex]
[tex]x = 28[/tex]
To calculate y, we have:
[tex]y = 3z[/tex]
[tex]y = 3 * 18[/tex]
[tex]y = 54[/tex]