Sean, ryan, and justin shared a sum of money in the ratio 3 : 4 : 5. if sean received $30, what was the sum of money shared?

In order to solve this problem, you need to find out how 3 of something  is 30
In this case, you multiply 10.
Sean= 3×10=30
Ryan= 4×10=40
Justin=  5×10= 50
30+40+50= 120
The answer is $120
Hope this helps