hola quien habla español bueno ya no Adios :)
Answer:
450 people paid the discounted fare and 750 people paid the regular fare.
Step-by-step explanation:
let r be regular fares paid and d be discounted fares paid
Total fares = 0.8r + 0.4d = 780
Since 1200 people paid the fares,
r + d = 1200 = Total people
Rearrange this formula:
r = 1200 - d
Substitute r into Total Fares formula
Total fares = 0.8r + 0.4d
780 = 0.8(1200-d) + 0.4d
780 = 960 - 0.8d + 0.4d
780 = 960 - 0.4d
0.4d = 180
d = 450
Sub d=450 into Total people formula
r + d = 1200 = Total people
r + 450 = 1200
r = 1200-450
r = 750
450 people paid the discounted fare and 750 people paid the regular fare.
Make use of the fact that side lengths in similar triangles are proportional.
.. 30/18 = (20 +x)/20
.. 20*(30/18) -20 = x . . . . multiply by 20, subtract 20
.. 33 1/3 -20 = x . . . . . . . . evaluate the product
.. 13 1/3 = x