Answer:
55
Step-by-step explanation:
252
t50 = t1 + (n - 1)(d)
= 7 + (50 - 1) (5)
= 7 + (49)(5)
= 7 + 245
= 252
n=10
5n-20=3n
-20=-2n
10=n
A True
tell me if I'm worng