She spent 10 minutes. 25% x 40 = 10.
Answer:
Part A:




Part B:


and 
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:


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





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

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

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



⇒ 
Answer:
2/5
Step-by-step explanation:
5x+6y=11
as we have to find x coordinate
while y coordinate 3/2 is already given in question
so only put value of y coordinate in given equation to get x coordinate value
5x+6y=11
5x+6*(3/2)=11
5x+3*3=11
5x+9=11
5x=11-9
5x=2
x=2/5
It is the answer D, because 9 it’s in all answers
<h3>
Answer: $59.25</h3>
========================================================
Explanation:
There are two approaches
Method 1
25% of 79 = 0.25*79 = 19.75
Mary saves $19.75 and the price before tax is 79 - 19.75 = 59.25
-----------------------------
Method 2
She saves 25% so she must pay the remaining 75%
75% of 79 = 0.75*79 = 59.25
This is a slight shortcut, and it's very useful when it comes to chaining multiple discounts together.