Math Ratios
posted by Dottie on .
The ratio of the length of a parallelogram to that of its breadth is 7:4. The length is longer than the breadth by 746.1 cm. Find the perimeter of the parallelogram

l/b = 7/4
l = b+746.1
so, since l = 7/4 b,
7/4 b = b+746.1
3/4 b = 746.1
b = 994.8
so, l = 1740.9
check: 1740.9/994.8 = 1.75 = 7/4 
l:b = 7:4
l/b=7/4
4l=7b
but l = b+746.1
4(b+746.1) = 7b
2984.4 = 3b
b = 994.8
l = 994.8 + 746.1 = 1740.9
perimeter = 2l + 2b = ..... 
they are right

5471.4