Question

please solve it fast​

Answer 1

Answer:

I don't know.

Sorry

Sorry

Step-by-step explanation:

PLZ. FOLLOW ME...

Answer 2

Answer:

5km/h

Step-by-step explanation:

Let

the speed of the stream be xkm/h

speed of downstream=15+X

speed of come back stream=15-X

total time taken=4hours30minutes=4+30/60=4+1/2

According to the Question

$⟶ \frac{30}{15 + x} + \frac{30}{15 - x} = 4 \frac{1}{2} \\ \\ ⟶ \frac{30(15 - x) + 30(15 + x}{(15 + x)(15 - x)} = \frac{9}{2} \\ \\ ⟶ \frac{450 - 30x + 450 + 30x}{225 - {x}^{2} } = \frac{9}{2} \\ \\ ⟶ \frac{900}{225 - {x}^{2} } = \frac{9}{2} \\ \\ ⟶2025 - 9 {x}^{2} = 1800 \\ \\ ⟶ - 9 {x}^{2} = 1800 - 2025 \\ \\ ⟶ - 9 {x}^{2} = - 225 \\ \\ ⟶ {x}^{2} = 25 \\ \\ ⟶x = \sqrt{25} \\ \\ ⟶x = 5$

Hence:-

the speed of stream is 5km/h