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If j is a multiple of 12, and k is a multiple of 21, then jk
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14 Nov 2016, 15:23
14 Nov 2016, 15:23
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83% (01:21) correct
16% (01:32) wrong based on 49 sessions
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If j is a multiple of 12, and k is a multiple of 21, then jk must be a multiple of which of the following?
A. 8
B. 15
C. 22
D. 28
E. 35
A. 8
B. 15
C. 22
D. 28
E. 35
Drill 4
Question: 5
Page: 293
Question: 5
Page: 293
Re: If j is a multiple of 12, and k is a multiple of 21, then jk
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14 Nov 2016, 15:25
14 Nov 2016, 15:25
1
Expert Reply
Explanation
Plug in values for j and k.
Since every number is a multiple of itself, go ahead and start with j = 12 and k = 21; jk is now 252. You can use your on-screen calculator to determine that, of the answer choices, only 28 divides evenly into 252. Choice D is correct.
Plug in values for j and k.
Since every number is a multiple of itself, go ahead and start with j = 12 and k = 21; jk is now 252. You can use your on-screen calculator to determine that, of the answer choices, only 28 divides evenly into 252. Choice D is correct.
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Re: If j is a multiple of 12, and k is a multiple of 21, then jk
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01 Jul 2020, 06:29
01 Jul 2020, 06:29
sandy wrote:
If j is a multiple of 12, and k is a multiple of 21, then jk must be a multiple of which of the following?
A. 8
B. 15
C. 22
D. 28
E. 35
A. 8
B. 15
C. 22
D. 28
E. 35
Drill 4
Question: 5
Page: 293
Question: 5
Page: 293
j is a multiple of 12
This means we can write j = 12n (for some integer n)
k is a multiple of 21
This means we can write k = 21m (for some integer m)
jk must be a multiple of which of the following?
jk = (12n)(21m)
= (4)(3)(n)(7)(3)(m)
= (28)(3)(n)(3)(m)
Clearly, jk is a multiple of 28
Answer: D
