LCM and HCF
-  The greatest possible length which can be used to measure exactly the lengths 7m, 3m 85cm, 12m 95 cm, is ?
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                        View Hint View Answer Discuss in Forum Required length = H.C.F of 700, 385, 1295 cm Correct Option: CRequired length = H.C.F of 700, 385, 1295 cm 
 = 35 cm.
-  The sum of two number is 216 and their H.C.F is 27. The numbers are ?
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                        View Hint View Answer Discuss in Forum Let the number be 27a and 27b 
 Then, 27a + 27b = 216
 or a + b = 216/27 = 8
 ∴ Values of co-primes with sum 8 are (1, 7) and (3, 5)
 So, the number are (27 x 1 , 27 x 7) i.e. (27, 189)Correct Option: CLet the number be 27a and 27b 
 Then, 27a + 27b = 216
 or a + b = 216/27 = 8
 ∴ Values of co-primes with sum 8 are (1, 7) and (3, 5)
 So, the number are (27 x 1 , 27 x 7) i.e. (27, 189)
-  The product of two-digit numbers is 2160 and their G.C.M is 12. The numbers are ?
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                        View Hint View Answer Discuss in Forum Let the number be 12a and 12b 
 Then 12a x 12b = 2160
 or ab = 15
 ∴ Values of co-primes a and b are (1, 15), (3, 5)
 So, the two digit number are 12 x 3 and 12 x 5 i.e. 36 and 60 .Correct Option: BLet the number be 12a and 12b 
 Then 12a x 12b = 2160
 or ab = 15
 ∴ Values of co-primes a and b are (1, 15), (3, 5)
 So, the two digit number are 12 x 3 and 12 x 5 i.e. 36 and 60 .
-  The H.C.F of two number is 16 and their L.CM is 160. If one of the numbers is 32, then the other number is ?
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                        View Hint View Answer Discuss in Forum Product of two numbers = LCM of two numbers x HCF of two numbers. 
 ⇒ N x 32 = 160 x 16
 ∴ N = 80Correct Option: BProduct of two numbers = LCM of two numbers x HCF of two numbers. 
 ⇒ N x 32 = 160 x 16
 ∴ N = 80
-  The product of two numbers is 1600 and their H.C.F is 5. The L.C.M. of the numbers is ?
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                        View Hint View Answer Discuss in Forum Product of two numbers = LCM of two numbers x HCF of two numbers. Correct Option: AProduct of two numbers = LCM of two numbers x HCF of two numbers. 
 ⇒ 1600 = LCM x 5
 ∴ LCM = 320
 
	