One weights 30lbs the other weights 54lbs
Answer:
21
Step-by-step explanation:
Let x represent the number of dimes and y represent the number of nickels. The total number of coins is 37; this gives us the equation
x+y = 37
Each dime is worth ten cents, or 0.10, and each nickel is worth five cents, or 0.05. The total amount of money is given by
0.10x+0.05y = 2.65
This gives us the system

To solve this, we will use substitution. We will isolate x in the first equation:
x+y=37
Subtract y from each side:
x+y-y = 37-y
x = 37-y
Substitute this into the second equation:
0.10(37-y)+0.05y = 2.65
Using the distributive property,
0.10(37)-0.10(y)+0.05y = 2.65
3.70-0.10y+0.05y = 2.65
Combining like terms,
3.70-0.05y = 2.65
Subtract 3.70 from each side,
3.70-0.05y-3.70 = 2.65-3.70
-0.05y = -1.05
Divide both sides by -0.05:
-0.05y/-0.05 = -1.05/-0.05
y = 21
There were 21 nickels.
Let's solve your equation step-by-step
16.8-(-23.72)-31.3=x
Step 1:simplify both sides of the equation
16.8-(-23.72)-31.3=x
16.8+23.72+-31.3=x
(16.8+23.72+-31.3)=x (combine like terms)
9.22=x
9.22=x
Step 2: flip the equation
Answer: x=9.22