3:4 = 24:X
3X = 4 x 24
3X = 96
1(3X) = 1(96) or 3X = 96
3
3
3
3
X = 32 quarts of water
or
cross multiply
3 = 24
4
X
Multiply the numerator of the first ratio by the denominator of the second ratio. Then
multiply the denominator of the first ratio by the numerator of the second ratio.
3X = 4 x 24
3X =
96
X = 32 quarts of water
SECOND EXAMPLE:
If three ties cost .57, what is the cost of five ties at the same rate?
Let y = the cost of five ties.
3:12.57 = 5:y
3 =5
12.57 y
3y = 5 x 12.57 = 62.85
1(3y) = 1(62.85)
3
3
y = .95
1-56. PRACTICE 1-11
a. 4:3 = 32:W
W = __________
MD0904
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