Answer:
1. First we need to make up a number that represents s so let's go with 7.
S=7
M=140
2. Alex had 20 dollars worth of cash and his brother had 10 he withdrew money from his bank account and now has 20 dollars.
Explanation:
When we have 7 we need to multiply by 20 because each student gives 20 dollars.
7x20=140 there for the m is 140