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Last night, Luis read 75% more pages than Dayja, and Dayja read 75% more pages than Michael. If Dayja read 84 pages, how many pages did Luis, Dayja, and Michael read all together?

User Bambam
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1 Answer

3 votes

Answer:

Total pages read = 279 pages

Explanation:

Let L, D, and M stand for the pages read by Luis, Dayja, and Michael, respectively.

We learn that:

L = 1.75D, [Luis read 75% more pages than Dayja]

D = 1.75M, and [Dayja read 75% more pages than Michael]

D = 84 [Dayja read 84 pages]

We want the sum of L, D, and M

Total pages = L + D + M

We have three equations and 3 unknowns. We should be able to find a solution by rearranging and substituting.

Total pages = L + D + M

We can substitute L=1.7D and rearrange D = 1.75 M to M = D/1.75

Total pages = L + D + M

Total pages = 1.7D + D + D/1.75

Total pages = D(1.7 + 1 + 1/1.75) [Isolate the D, for optional simplification]

Total pages = D(3.271)

We know D = 84, so:

Total pages = 84(3.271)

Total pages = 274.8

We'll round that to 275 pages.

Check:

L = 1.75D: L read 1.75*275 or 147 pages

D read 84 pages

D = 1.75M, or M = D/1.75; M read 84/1.75) or 48 pages

Total pages read = 147 + 84 + 48

Total pages read = 279 pages

User Ciechowoj
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