Mrs Johnson has $110 to spend on parking will cost $12 and admission tickets will cost $140 per person including tax

The answer is Ms Hernandez can bring up to 6 people to the zoo.

x - the number of people that she can bring to the zoo

The parking will cost $7: a = 7

Admission tickets will cost $15.50 per person: b = 15.50x

She can spend on parking and admission tickets $100:

a + b ≤ 100

a = 7

b = 15.50x

7 + 15.50x ≤ 100

15.50x ≤ 100 - 7

15.50x ≤ 93

x ≤ 93 / 15.50

x ≤ 6