Answer: 280
<u>Step-by-step explanation:</u>
Quantity X Cost = Money Received
Adult: x 3 3x
Children: 500-x 2 2(500 - x) = 1000 - 2x
Adult = Children + 400
3x = 1000 - 2x + 400
3x = 1400 - 2x
5x = 1400
x = 280
Answer :19
19\
Step-by-step explanation:
Answer:To do so, she makes the measurements shown in the figure below.