Question

A mistake was made in mixing the lemonade—
PLEASE HELP!!

Answer 1

Answer:

Part A:

$4 + x = y$

$0.5*4 + 1*x = 0.7*y$

$x = 8/3\ quarts\ of\ 100\%\ solution$

$y = 20/3\ quarts\ of\ 70\%\ solution$

Part B:

$x + y = 10$

$2x + 3y = 23$

$x = 7$ and $y = 3$

Step-by-step explanation:

Part A:

The inicial concentration of the lemonade is 50%, and the volume is 4 quarts, and we will add x quarts of a lemonade with a concentration of 100%, so the total volume will be y, and the concentration will be 0.7, so we have that:

$4 + x = y$

$0.5*4 + 1*x = 0.7*y$

Using the value of y from the first equation in the second one, we have:

$2 + x = 0.7*(4 + x)$

$2 + x = 2.8 + 0.7x$

$0.3x = 0.8$

$x = 8/3\ quarts$

$y = 4 + 8/3 = 20/3\ quarts$

Part B:

If he shoots a total of ten targets, we can write the equation:

$x + y = 10$

Each stationary target is 2 points, and each moving target is 3 points, so if the total points is 23, we have:

$2x + 3y = 23$

If we subtract the second equation by two times the first one, we have:

$2x + 3y - 2*(x + y) = 23 - 2*10$

$2x + 3y - 2x - 2y = 23 - 20$

$y = 3$

$x + 3 = 10$ ⇒ $x = 7$