I did not quite understand the explanation - so, please don't repeat the solution from the OG.
In a certain game, a large container is filled with red, yellow, green and blue beads worth, 7, 5, 3, and 2 points each. A number of beads are then removed from the container. If the product of the point values of the removed beads is 147,000, how many red beads were removed?
A. 5
B. 4
C. 3
D. 2
E. 0
OG 12 - PS Q#217
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- sl750
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This problem uses number properties
Find the prime factors of 147000 = 2*3*5*7*7*5*2*5*2 = 2^3*3*5^3*7^2
Notice that the prime factors correspond to the points of the Red Yellow, Green and Blue beads
respectively
Red = 7 points; In 147000, we have two 7's
Yellow = 5 points; In 147000, we have three 5's
Green = 3 points; In 147000, we have one 3
Blue = 2 points; In 147000, we have 3 2's
From this we can clearly see that we have removed two 7's or 2 Red beads
Find the prime factors of 147000 = 2*3*5*7*7*5*2*5*2 = 2^3*3*5^3*7^2
Notice that the prime factors correspond to the points of the Red Yellow, Green and Blue beads
respectively
Red = 7 points; In 147000, we have two 7's
Yellow = 5 points; In 147000, we have three 5's
Green = 3 points; In 147000, we have one 3
Blue = 2 points; In 147000, we have 3 2's
From this we can clearly see that we have removed two 7's or 2 Red beads
- VivianKerr
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This has to do with factors and multiples.
7r + 5y + 3g + 2b = 147,000
We want to find the value of "r", the number of red beads removed.
Let's do a prime factorization of 147,000.
147,000 = 7 x 7 x 5 x 5 x 5 x 3 x 2 x 2 x 2
We have removed two 7's, so the answer is D.
7r + 5y + 3g + 2b = 147,000
We want to find the value of "r", the number of red beads removed.
Let's do a prime factorization of 147,000.
147,000 = 7 x 7 x 5 x 5 x 5 x 3 x 2 x 2 x 2
We have removed two 7's, so the answer is D.
Vivian Kerr
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GMAT Rockstar, Tutor
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https://www.yelp.com/biz/gmat-rockstar-los-angeles
Former Kaplan and Grockit instructor, freelance GMAT content creator, now offering affordable, effective, Skype-tutoring for the GMAT at $150/hr. Contact: [email protected]
Thank you for all the "thanks" and "follows"!