Answer:
21
Step-by-step explanation:
Similar triangles. MNL is just ABC but 3/4 the size.
x = 8*3/4 = 6
perimeter woudl be 6+6+9 = 21
Is there a graph? not sure what to solve.
(18 neclaces)/(12 days) = 1.5 necklaces/day
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Rate is generally expressed in terms of quantity per time period. ("Per" means "divided by" here.) So, to find the rate, you divide the quantity by the corresponding time period, as above. There are other sorts of rates, but this is perhaps the most common.
I think it would be $14 per book