A student makes a $8.75 purchase at the bookstore with a $20 bill. The store has no bills and gives the change in quarters and fifty cent pieces. There are 30 coins in all. many quarters are there? How many fifty-cent pieces

30=q+f

.25q+.5f=(20-8.75)

solve for q, f

Find the product

could you check to see if I am right
(2x+3)(5x-4)=10x-12=x=22
(3a-4b)(3a+4b)=9a-16b
could you check these for me. thank

(2x+3)(5x-4)=

10x-12=
-2

(3a-4b)(3a+4b)=
9a-16b

Could someone check these problem for me, please

could someone check these problem please

What is the v olume of a box whose length is 12-2x, width is 7-2x and height is x?

help me

30

To find the number of quarters, we need to determine how much change the student is receiving.

Step 1: Subtract the purchase amount from the amount paid:
$20 (amount paid) - $8.75 (purchase amount) = $11.25 (change)

Step 2: Since the store gives the change in quarters and fifty-cent pieces, we need to express $11.25 in terms of quarters and fifty-cent pieces.

Step 3: Determine the number of quarters:
Since there are 4 quarters in $1, we need to find how many sets of 4 go into $11.25. We can do this by dividing $11.25 by $0.25 (the value of a quarter):
$11.25 / $0.25 = 45 quarters

Therefore, there are 45 quarters.

Step 4: Determine the number of fifty-cent pieces:
Since there are 2 fifty-cent pieces in $1, we need to find how many sets of 2 go into $11.25. We can do this by dividing $11.25 by $0.50 (the value of a fifty-cent piece):
$11.25 / $0.50 = 22.5 fifty-cent pieces

However, we cannot have a fraction of a coin, so we need to round down to the nearest whole number. Therefore, there are 22 fifty-cent pieces.

To summarize:
- There are 45 quarters.
- There are 22 fifty-cent pieces.