hFind the least number which leaves a remainder 7 when it's divided by any one of the number : 20, 30 and 40 .
The LCM is a multiple and the GCF is a factor so the LCM will be greater.
Let the age of Junior be x,
age of grandpa schmidt = 7x + 9
7x + 9 = 75
7x = 66
x = 66/7
= 9.43 (to three significant figures)
Junior is 9.43 years old.
The answer is a
this is because the shape increased in size by a factor of 2