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If x is the greatest common divisor of 90 and 18, and y is
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20 Apr 2020, 11:20
20 Apr 2020, 11:20
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If x is the greatest common divisor of 90 and 18, and y is the least common multiple of 51 and 34, then x + y =
A) 111
B) 120
C) 213
D) 222
E) 231
A) 111
B) 120
C) 213
D) 222
E) 231
Re: If x is the greatest common divisor of 90 and 18, and y is
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20 Apr 2020, 11:48
20 Apr 2020, 11:48
2
We know x = 18
The greatest common divisor of 90 and 18 is 18, becaause 90 is divisable by 18
For Y, we need to find the lowest common number that both 51 and 34 can multiply to. To do this, I multiplied 51*2 = 102. Right away I noticed that 34*3 = 102. We now have both numbers common multiple with their respective lowest multiplier. So, y = 102
x+y = 102+18 = 120, Answer B
A more math friendly way to solve for Y would be to find the greatest common factor of 51 and 34 (which is 17. 51/17=3 and 34/17=2) Then divide the product of 51(34) by their greatest common factor (17) -> (51*34)/17 = 102 = y
The greatest common divisor of 90 and 18 is 18, becaause 90 is divisable by 18
For Y, we need to find the lowest common number that both 51 and 34 can multiply to. To do this, I multiplied 51*2 = 102. Right away I noticed that 34*3 = 102. We now have both numbers common multiple with their respective lowest multiplier. So, y = 102
x+y = 102+18 = 120, Answer B
A more math friendly way to solve for Y would be to find the greatest common factor of 51 and 34 (which is 17. 51/17=3 and 34/17=2) Then divide the product of 51(34) by their greatest common factor (17) -> (51*34)/17 = 102 = y
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Re: If x is the greatest common divisor of 90 and 18, and y is
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28 Oct 2022, 08:01
28 Oct 2022, 08:01
2
Given that x = GCD(90,18) and y = LCM(51,34) and we need to find the value of x + y
GCD(90,18)
90 = 5*18
18 = 1*18
To find the GCD take all the common terms and take their lowest power in all of the above.
=> GCD(90,18) = 18
=> x = 18
LCM(51,34)
51 = 3*17
34 = 2*17
To find the LCM take all the terms and take their highest power in all of the above.
=> LCM(51,34) = 2*3*17 = 102
=> y = 102
=> x + y = 18 + 102 = 120
So, Answer will be B
Hope it helps!
To learn more about LCM and GCD watch the following videos
GCD(90,18)
90 = 5*18
18 = 1*18
To find the GCD take all the common terms and take their lowest power in all of the above.
=> GCD(90,18) = 18
=> x = 18
LCM(51,34)
51 = 3*17
34 = 2*17
To find the LCM take all the terms and take their highest power in all of the above.
=> LCM(51,34) = 2*3*17 = 102
=> y = 102
=> x + y = 18 + 102 = 120
So, Answer will be B
Hope it helps!
To learn more about LCM and GCD watch the following videos
