Q11
Suppose the two numbers are x and y so xy = 3000
the HCF = 10
we know that product of two numbers = product of their HCF and LCM
XY = HCF * LCM
3000 = 10 * LCM
3000/10 = LCM
300 = LCM
Answer 300
Q12 : Let us say second number is x so
product of x and 160 = product of HCF and LCM of ( x and 160 )
160 x = 32 * 1760
x= 32 * 1760 / 160
x= 352
Answer : 352
6.7x10^6 always the the decimal points go between the first 2 numbers, and you count the numbers of decimal places following it to get your scientific exponent
Use synthetic division. Look at my attachment below for a detailed explanation. If the remainder is 0 (which it is), then it's a factor.
