Answer:

6 mangoes.

Given ratios:

mangoes to guavas

3:8

guavas to oranges

3:4

Step-by-step explanation:

1. use guavas to oranges ratio

3:4 = __:192

multiply 192 and 3.

576.

divide it by 4.

144.

thus,

3:4 = 144:192

"144 guavas can be exchanged with 192 oranges."

2. use mangoes to guavas ratio

3:8 =__:144

multiply 144 and 3.

432.

divide it by 8.

54.

thus,

3:8 = 54:144

"54 mangoes can be exchanged with 144 guavas (which was initially exchanged from 192 oranges)."