If we let Q be the number of quarters and N be number of nickels, this is the formula we would use:
[1] 25Q + 5N = 635 (using cents instead of dollars)
We also know something about Q and N.
[2] Q + N = 51
So multiply both sides of the second equation by 5. The reason we do this is because we're going to need to cancel out one of the variables (either Q or N) to solve for the other one. If we multiply times 5, we'll have 5N in both equations.
5Q + 5N = 255
Now we have two equations, and the second one can be subtracted from the first.
25Q + 5N = 635
-(5Q + 5N) = -255
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20Q = 380
so
Q = 19
There are 19 quarters.
And since there are 51 coins in all, 51-19 = 32 nickels.
Answer:
DC = 21 ; BC = 26
Step-by-step explanation:
The perimeter of a rectangle is given by :
P = 2(length + width)
2x + 3
3x - 1
Perimeter, P = 94
Hence,
94 = 2(2x +3 + (3x - 1))
94 = 2(2x + 3 + 3x - 1)
94 = 2(5x + 2)
94 = 10x + 4
94 - 4 = 10x
90 = 10x
x = 90 /10
x = 9
DC = 2x + 3 = 2(9) + 3 = 18 + 3 = 21
BC = 3x - 1 = 3(9) - 1 = 27 - 1 = 26
Answer:
10kg?
Step-by-step explanation:
Answer:
100
100
dividing
Step-by-step explanation: