answer is c because if it's not a and b then the only answers will be c and d and d is the same as the number so it's c
Answer:

Step-by-step explanation:

First, sum up the total expenses for the original plan
Duque de Caxias + Campinas + Rio de Janeiro + Guarulhos = 242+185+193+120 = R$740
It is clearly over the intended budget. The average cost per itinerary is around R$200 so we will consider making a swap on either Duque de Caxias and Rio de Janeiro. Possible answers are (b) or (c)
for (b) Replace Duque de Caxias with Fortaleza, we will have
Fortaleza + Campinas + Rio de Janeiro + Guarulhos =
⇒ 201+185+193+120 = R$699 ⇒ This is exactly the budget intended for the trip
for (C) Replace Rio de Janeiro with Porto Alegre
Duque de Caxias + Campinas + Porto Alegre + Guarulhos =
⇒ 242 + 185 + 153 +120 = R$ 700 ⇒ This is over R$1
The answer is (b)
What we need to do is find the difference between the two numbers to find the difference in price and then figure out what the percent of 23.5 that is
23.50-18.80=4.7
now we'll set up a proportion
4.7 x
----- = -----
23.5 100
then cross multiply and divide
100×4.7=470/23.5=20
the percent of decrease is 20%
I hope I've helped!