A geologist has 10 rocks of equal weight. If 6 rocks and a 10-ounce weight balance on a scale with 4 rocks and a 22-ounce weight , what is the weight of one of these rocks in ounces ?
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Weight of each rock is 14.8 ounces.
Step-by-step explanation:
Given,
Total number of rocks = 10
6 rocks weigh 10 ounce each
4 rocks weigh 22 ounce each.
To find the the weight of each rock.
Now,
Weight of 6 rocks = 10×6 ounces = 60 ounces
Weight of 4 rocks = 22×4 ounces = 88 ounces
So,
Weight of 10 rocks = 88+60 = 148 ounces
Hence,
Weight of each rock = 148÷10 = 14.8 ounces.