Answer:
He received 10 dimes and 15 quarters.
Step-by-step explanation:
Dimes = $0.10
Quarters = $0.25
Variable x = dimes
Variable y = quarters
Create a pair of linear equations:
0.10x + 0.25y = 4.75
x + y = 25
Isolate any variable, using an equation of your choice:
x + y = 25
x = 25 - y
Plug in this new value of x into the other equation:
0.10(25 - y) + 0.25y = 4.75
Use the distributive property:
2.5 - 0.10y + 0.25y = 4.75
Combine like terms:
2.5 + 0.15y = 4.75
Isolate variable y:
0.15y = 2.25
y = 15
Plug in the value of y into any equation:
x + y = 25
x + 15 = 25
Isolate variable x:
x = 10
Answer:
12
Step-by-step explanation:
This can be solved by working backwards.
7 is one more than half the number of invitations.
Subtract 1. 6 is half the number of invitations.
Double.
12 is the full number of invitations.
Algebra (if you must!):
x = number of invitations
x/2 + 1 = 7
Subtract 1.
x/2 = 6
Multiply by 2.
x = 12
Y/x = 5 bc in order to isolate the variables you must divide by x on both sides to separate the 5, leaving you with y/x=5
Answer:
44.88
Step-by-step explanation:
Heaviest box = 424.25
Lightest box = 379.37
424.25 - 379.37 = 44.88
Hope this helps!