math i need help 3 questions
posted by Bladimir on .
1. The numerator and denominator of a fraction are in the ratio of 3 to 4. If 4 is added to the numerator and subtracted from the denominator, the value of the resulting fraction is 4/3. The numerator of the original fraction is
2. If it takes b hours to walk a certain distance at the rate of 3 miles an hour, the number of hours it takes to return the same distance at 4 miles an hour is
3. The perimeter of a rectangle is 20 inches and its length is 6 inches. The area of the rectangle in square is
number 1 choice b is 9
I'll do #1. How about you show some effort on the others? Just write the words in symbols.
If the fraction is n/d, then we are told
n/d = 3/4
(n+4)/(d-4) = 4/3
Work through all that, and you have n=12,d=16
12+4 / 16-4 = 16/12 = 4/3