What is the fourth term of the expansion of the binomial (2x + 5) ^5?

From pascal's pyramid

4th term of 5th order is 10

(coefficient - let's call c)

for (a + b) ^n the m-th term is

c[a^ (n-m+1) ][b^ (m-1) ]

sample (a + b) ^3

1st term : c1 (a^3b^0) = c1a^3

2nd term : c2 (a^2b^1)

3rd term : c3 (a^1b^2)

4th term : c4 (a^0b^3) = c4b^3

... notice order of 2 variables

one decreases from max to 0, the other increases from 0 to max AND

sum of orders in each term must equal to the order of the binomial

for (2x + 5) ^5, 4th term is

10[ (2x) ^ (5-4+1) ][5^ (4-1) ]

= 10[ (2x) ^2][5^3) ]

= ...