How many pounds of chocolate worth $1.5 a pound must be mixed with 10 pounds of chocolate worth 80 cents a pound to produce a mixture worth $1 a pound?

x = 4 pounds.

Step-by-step explanation:

Let x be the mix amount of $1.5

Be and the amount of mixture of $0.8

Let z be the amount of mix of $1

We know that an amount x of mix of $ 1.5 should be added to y = 10 pounds of mix of $ 0.8 to get mix of $ 1. This is

x + y = z

x +10 = z (i)

Then, we know that the amount of money invested in the mix must be:

1.5x + 0.8y = 1z (ii)

We must clear x.

For this we substitute (i) in (ii)

1.5x + 0.8y = x + 10

-10 + 0.8y = = -0.5x

We know that y = 10.

So:

0.5x = 10 - 0.8(10)

x = 2(10-8)

x = 4 pounds.

You must add 4 pounds of 1.5 $ mix

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step-by-step explanation: