The value of three in 6,300 is 3,000 because it is in the thousands place. The three in 530 is in the hundreds place making the value of three 300. Hope that this helps you :D
Let's call the younger student's age A and the older student's age B. The teacher's age will be T.
B = 2A
T = 5B
T+5 = 5(A+5)
Simplify the last equation.
T+5 = 5A+25
T = 5A+20
Now we have two equations solved for T, so we can set them equal to each other.
5B = 5A + 20
We can plug 2A in for B
5(2A) = 5A + 20
10A = 5A + 20
5A = 20
A = 4
To find T, we plug 4 in for A in T = 5A + 20
T = 5(4) + 20
T = 40
The answer is 40 years old.
There isn't enough info to determine that, I believe. You would need an equation that would allow me to determine the minimum output for an A.