12.4 / 6.2 = 2
so other side of enlarged rectangle = 1.8 x 2 = 3.6
Perimeter of enlarged rectangle = 2(3.6 + 12.4) = 32
Answer: 32 feet
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Another way to do:
12.4 / 6.2 = 2
SF = 2
The original rectangle has a perimeter of 16
Perimeter of the enlarged rectangle = 16 x 2 = 32
Answer: 32 feet
Assume the second number is x, then the other two are x - 2, x + 2
So x-2 + x + x + 2 = 51
-> 3x = 51
-> x = 17
Changing a fraction to its decimal form can be done by long division method. Dividing the denominator by its numerator will change the fraction into decimal form. Alternatively, you can use a calculator to do that for you. Below are the fractions with their decimal forms listed:
1.) 2/5 = 0.4 (D)
2.) 7/20 = 0.35 (A)
3.) 3/25 = 0.12 (C)
4.) 7/10 = 0.7 (B)