Answer
Number of messages sent by Latoya = 30 messages
Number of messages sent by Tony = 21 messages
Number of messages sent by Boris = 84 messages
Step-by-step explanation
Let the number of messages sent by Latoya be x
Number of messages sent by Latoya = x
Tony sent 9 fewer messages than Latoya
Number of messages sent by Tony = x - 9
Boris sent 4 times as many messages as tony
Number of messages sent by Boris = 4 (x - 9)
Latoya, Boris and Tony sent a total of 135 text messages over their cell phones during the weekend
x + x - 9 + 4 (x - 9) = 135
x + x - 9 + 4x - 36 = 135
6x - 45 = 135
6x = 135 + 45
6x = 180
Divide both sides by 6
(6x/6) = (180/6)
x = 30
Number of messages sent by Latoya = x = 30 messages
Number of messages sent by Tony = x - 9 = 30 - 9 = 21 messages
Number of messages sent by Boris = 4 (x - 9) = 4 (21) = 84 messages
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