Amanda bob and Scott sent a total of 75 messages over the weekend. Bob sent 3 times as many than Scott. Amanda sent 10 fewer messages than Scott. How many messages did they send
Let the total number of messages sent by Scott = S
Bob sent =3S
Amanda sent =S - 10
S + 3S + S - 10 =75, solve for S
5S =75 + 10
S =17 - messages sent by Scott
17 x 3 =51 messages sent by Bob
17 - 10 = 7 messages sent by Amanda. So that:
17 + 51 + 7 =75 - total number of messages sent by all.