The equation can be used to determine t, the weight of the textbooks is t = 0.7w
Given:
let
Total weight = w
Weight of notebook = n
Weight of backpack = b
Weight of textbook = t
w = n + b + t
where
n = 4 pounds
b = 2 pounds
t = 0.7w
So
w = 4 + 2 + 0.7w
w - 0.7w = 4 + 2
0.3w = 6
w = 6/0.3
w = 20
Recall,
t = 0.7w
= 0.7(20)
= 14 pounds
Therefore, the weight of the textbook is 14 pounds
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