mass

[Pra4ash]

q:
Kenny weighs 4e kg and Benjamin is 3kg heavier than him. After three months, Kenny loses (e+2)kg. On the contrary, Benjamin gains 4 kg during the same period. Calculate the mass difference between the both of them at the end of the three months.

my attempt:

Kenny	Benjamin
4e kg	7e kg
4e kg -(e+2) kg :: after three months	7e kg + 4 kg:: after three months

so, the difference is:
(4e kg -e kg -2 kg) - ( 7e kg + 4 kg)
3e kg - 2kg - 7e kg + 4 kg
3e kg - 7e kg -2kg + 4 kg
-4e kg - (+2 kg)

my answer: -4e kg - 2kg

actual answer
(e + 9)kg

where did I go wrong? thanks all.

Pra4ash

 

[lookagain]

q:
Kenny weighs 4e kg and Benjamin is 3kg heavier than him. After three months, Kenny loses (e+2) kg. On the contrary, Benjamin gains 4 kg during the same period. Calculate the mass difference between the both of them at the end of the three months.

my attempt:

Kenny	Benjamin
4e kg	4e kg + 3 kg
4e kg - (e + 2) kg = (4e - e - 2)kg = (3e - 2)kg :: after three months	4e kg + 3 kg + 4 kg = 4e kg + 7 kg :: after three months

So, the difference is:
(4e kg + 7 kg) - (3e - 2)kg =
4e kg + 7 kg - 3e kg + 2 kg = :
e kg + 9 kg =
(e + 9) kg

. Pra4ash, the main thing you had wrong was the expression under Benjamin in the top right box of your chart.