Let the positive odd numbers be x,x+2,x+4.
According to the question,
5(3x+30)=72+x^2+4x
x^2-13x+42=0
(x-6) and (x-7)=0
x=6 or x=7

Answer : No, the new type of letter wouldn't be considered as a success because its response rate (2.71%) is lower than the average response rate which is 4%.
Hope this helps. - M
(8)(2)+4(8)(-5)(2)(2)
The answer is -624
B. 5:10 because 15-5=10 which is the number of pencils with erasers and the 5 left are the amount of pencils which are missing an eraser