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How many positive integers less than 20 can be expressed as the sum of
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21 Sep 2021, 20:54
21 Sep 2021, 20:54
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Question Stats:
46% (02:33) correct
53% (02:45) wrong based on 13 sessions
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How many positive integers less than 20 can be expressed as the sum of a positive multiple of 2 and a positive multiple of 3?
(A) 14
(B) 13
(C) 12
(D) 11
(E) 10
(A) 14
(B) 13
(C) 12
(D) 11
(E) 10
How many positive integers less than 20 can be expressed as the sum of
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22 Sep 2021, 00:14
22 Sep 2021, 00:14
Positive multiple of \(2 = 2, 4, 6, 8, 10, 12, 14, 16, 18\)
Positive multiple of \(3 = 3, 6, 9, 12, 15, 18\)
The sum should be less than \(20\) with the combination of the above numbers.
They can be \(5, 8, 11, 14, 17, 7, 10, 13, 16, 19, 9, 12, 15, 18\)
Total \(14\) nos
Answer A
Positive multiple of \(3 = 3, 6, 9, 12, 15, 18\)
The sum should be less than \(20\) with the combination of the above numbers.
They can be \(5, 8, 11, 14, 17, 7, 10, 13, 16, 19, 9, 12, 15, 18\)
Total \(14\) nos
Answer A
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Re: How many positive integers less than 20 can be expressed as the sum of
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01 Oct 2022, 02:50
01 Oct 2022, 02:50
1
We need to find How many positive integers less than 20 can be expressed as the sum of a positive multiple of 2 and a positive multiple of 3
Let's try to express each number from 5 to 19 as a positive multiple of 2 and 3
We are considering only between 5 and 19 because
- 5 is the least number which can be formed with positive multiples of 2 and 3
- 19 because we need to find numbers less than 20
Using following format: Number = multiple of 2 + multiple of 3
5 = 2 + 3
6 = NOT POSSIBLE to express
7 = 4 + 3
8 = 2 + 6
9 = 6 + 3
10 = 4 + 6
11 = 8 + 3
12 = 6 + 6
13 = 10 + 3
14 = 8 + 6
15 = 12 + 3
16 = 10 + 6
17 = 14 + 3
18 = 12 + 6
19 = 16 + 3
Total numbers = (19-5 + 1 ) - 1 = 14
So, Answer will be A
Hope it helps!
Watch the following video to learn How to Sequence problems
Let's try to express each number from 5 to 19 as a positive multiple of 2 and 3
We are considering only between 5 and 19 because
- 5 is the least number which can be formed with positive multiples of 2 and 3
- 19 because we need to find numbers less than 20
Using following format: Number = multiple of 2 + multiple of 3
5 = 2 + 3
6 = NOT POSSIBLE to express
7 = 4 + 3
8 = 2 + 6
9 = 6 + 3
10 = 4 + 6
11 = 8 + 3
12 = 6 + 6
13 = 10 + 3
14 = 8 + 6
15 = 12 + 3
16 = 10 + 6
17 = 14 + 3
18 = 12 + 6
19 = 16 + 3
Total numbers = (19-5 + 1 ) - 1 = 14
So, Answer will be A
Hope it helps!
Watch the following video to learn How to Sequence problems
