Answer:
He has 12 ten dollar bills
Step-by-step explanation:
Let t = number of 10 dollar bills
f = number of fifty dollar bills
t+f = 25 since he has 25 bills
solving for f
f = 25 -t
Then we know he has 770 dollars
10t+50f = 770
Using f = 25-t in the above equation
10t + 50 ( 25-t) = 770
Distribute
10t+ 1250 - 50t = 770
Combine like terms
-40t+1250 = 770
subtract 1250 from each side
-40t - 1250-1250 = 770-1250
-40t = -480
divide each side by -40
-40t/-40 = -480/-40
t =12
He has 12 ten dollar bills
