Idon't understand this question. can you guys ?

a carnival has two payment options. plan a, you pay $10 admission plus $3 for each ride. plan b, you pay a $20 admission plus $1 for each ride. write an inequality that would express the situation where plan b is the best buy.
a) 20x > 10 + 3x
b) 20x < 10 + 3x
c) 20 + x < 10 + 3x
d) 20 + x > 10 + 3x