Answer:
He will need 15.6 feet of fence
Explanation:
Jim's back yard has the following dimensions;
Length=120 feet
Width=75 feet
The gardens dimensions can be calculated using the expression;
Length of garden=Length of back yard/scale factor
where;
Length of back yard=120 feet
Scale factor=25
replacing;
Length of garden=120/25
Length of garden=4.8 feet
Width of garden=Width of back yard/scale factor
where;
Width of back yard=75 feet
Scale factor=25
replacing;
Width of garden=75/25
Width of garden=3 feet
The gardens dimension are;
Garden width=3 feet
Garden length=4.8 feet
To get the length of the fence that will enclose all four sides, we calculate the perimeter of the garden;
Perimeter=2(length+width)
Perimeter=2(4.8+3)=15.6 feet
He will need 15.6 feet of fence