Question

pls answer fast I want it write now​

Answer 1

Step-by-step explanation:

1st Sum:

Let speed of stream = x km/h

∴ Downstream speed = (15+x) km/h

∴ Upstream speed = (15-x) km/h

∴ 30/(15+x) + 30/(15-x) = 4 1/2

→ 900/225-x² = 9/2

→ 9x² = 225

→ x² = 25

→ x = 5

∴ Speed of stream = 5km/hr

Second sum please check the file attached!