Answer: x=7, y=-5
Step-by-step explanation:
Answer:
a
Step-by-step explanation:
Answer:
4.5 % alloy
Step-by-step explanation:
Let x = amt of 30% alloy
The resulting total is to be 25 oz, therefore:
(25-x) = amt of 5% alloy:
A typical mixture equation:
.30x + .05(25-x) = .20(25)
.30x + 1.25 - .05x = 5 .30x - .05x = 5 - 1.25
.25x = 3.75
x = 3.75%2F.25
x = 15 oz of 30% alloy required
then
25-15 = 10 oz of 5% alloy:
Check solution
.30(15) + .05(10) = .20(25)
4.5 + .5 = 5
32 students choose a favorite topping for their slices.
Let x be the total number of students.
1/2 of the total students, or 1/2x, choose pepperoni.
1/4 of the total students, or 1/4x, choose extra cheese.
1/8 of the total students, or 1/8x, choose sausage.
4 students choose mushrooms.
We know that together, these equal the total number of students, x:
1/2x+1/4x+1/8x+4=x
We will use 8 as the common denominator:
4/8x+2/8x+1/8x+4=x
Combining like terms:
7/8x+4=x
Subtract 7/8x from both sides:
7/8x+4-7/8x=x-7/8x
4=1x-7/8x
4=1/8x
Divide both sides by 1/8:
4÷(1/8) = 1/8x÷(1/8)
4/1÷(1/8) = x
4/1×8/1 = x
32/1 = x
32 = x