The answer is 4440. You can determine this by using your rules of divisibility. We know that is must end in a 0 or 5 to be divisible by 5 and that the sum of the digits must be divisible by 3 in order to divide by 3. One or two 4's together are not divisible by 3. Three 4's are, but it must end in 0 to be divisible by 5 as well.
Answer:
Step-by-step explanation:
4x10=40
7x10=70
6x10=60
10x10=100
8x10=80
4x14=56
5x16=80
40+70+60+100+80+56+80= $486
Let the present age of student be x
Present of teacher will be 4x
After 20 years,
Age of student = x + 20
Age of teacher = 4x + 20
According to the given condition after 20 years,
x + 20 = (4x + 20)/2
x + 20 = 2x + 10
2x - x = 20 - 10
x = 10
So student's present age is 10 years while teacher's is 4 x 10 i.e 40 years.
Hope This Helps You!
