1.
For 420, find number of
a) prime factors,
b) different prime factors,
c) number of factors
2.Determine the count of positive integers less than x and coprime with x
a) x=75
b) x=160
c) x= 350
3. Find
a) LCM (70,120) *HCF (70,120) =?
b) LCM (63,49) * HCF (63,49) =?
c) LCM (60,48) * HCF (60,48) =?
4.Find
a)
𝐿𝐿𝐿𝐿𝐿𝐿(120,150)
𝐻𝐻𝐻𝐻𝐻𝐻(120,150)
b)
𝐿𝐿𝐿𝐿𝐿𝐿(250,200)
𝐻𝐻𝐻𝐻𝐻𝐻(250,200)
c)
𝐿𝐿𝐿𝐿𝐿𝐿(120,360) =?
d)
𝐻𝐻𝐻𝐻𝐻𝐻 (120,360) =?
5.
A and b are natural numbers, c is product of uncommon factors, Find HCF(a,b) for each
a)
𝑎𝑎 × 𝑏𝑏 = 250 , 𝑐𝑐 = 10
b)
𝑎𝑎 × 𝑏𝑏 = 200 , 𝑐𝑐 = 2
c)
𝑎𝑎 × 𝑏𝑏 = 240 , 𝑐𝑐 = 15
6.
Using this formula LCM(a,b)=√𝑎𝑎 × 𝑏𝑏 × 𝑐𝑐, find
a)
𝑎𝑎 × 𝑏𝑏 = 250 , 𝑐𝑐 = 10
b)
𝑎𝑎 × 𝑏𝑏 = 200 , 𝑐𝑐 = 2
c)
𝑎𝑎 × 𝑏𝑏 = 64 , 𝑐𝑐 = 4
7. Take suitable numbers for a and b, considering that
a)
If and b are consecutive integers find LCM(a,b)=?,HCF(a,b)=?
b)
If and b are consecutive odd integers find LCM(a,b)=?, HCF(a,b)=?
c)
If and b are consecutive even integers find LCM(a,b)=?, HCF(a,b)=?