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How many factors greater than one
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Updated on: 21 Sep 2019, 10:39
Updated on: 21 Sep 2019, 10:39
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Question Stats:
61% (01:55) correct
38% (02:19) wrong based on 18 sessions
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How many factors greater than one, do 120, 210 & 270 have?
a. 1
b. 3
c. 7.
d. 12.
e. Infinite
a. 1
b. 3
c. 7.
d. 12.
e. Infinite
Re: Common Prime Factors
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15 Mar 2019, 11:43
15 Mar 2019, 11:43
1
Expert Reply
\(120 = 12 x 10 = 2^2 x 3 x 5\)
\(210 = 21 x 10 = 2 x 3 x 5 x 7\)
\(270 = 27 x 10 = 2 x 3^2 x 5\)
just take out the common factors from above
2,3,5,6,10,15,30
The answer is D
\(210 = 21 x 10 = 2 x 3 x 5 x 7\)
\(270 = 27 x 10 = 2 x 3^2 x 5\)
just take out the common factors from above
2,3,5,6,10,15,30
The answer is D
Re: Common Prime Factors
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21 Sep 2019, 07:30
21 Sep 2019, 07:30
1
Correct answer is option C - 7
120=(2^3)*5*3
210=2*5*3*7
270=2*5*(3^3)
Common terms = 2*5*3
Total No. of Factors = (1+1)*(1+1)*(1+1)=8
No. of factors greater than 1 = 8-1=7
120=(2^3)*5*3
210=2*5*3*7
270=2*5*(3^3)
Common terms = 2*5*3
Total No. of Factors = (1+1)*(1+1)*(1+1)=8
No. of factors greater than 1 = 8-1=7
