Question

Please answer correctly​

Answer 1

Answer :

The speed of rowing in still water is 7 km/hr and the speed of the current is 3 km/hr.

Explaination :

Let :

➺ Speed of her in still water be u km/hr.

➺ Speed of current be v km/hr.

We know that :

➺ Speed downstream = u + v

➺ Speed upstream = u — v

Given, she can row downstream 30 km in 3 hrs.

➺ Speed = Distance/Time

➺ u + v = 30/3

➺ u + v = 10 km/hr

Also, she can row upstream 12 km in 3 hrs.

➺ Speed = Distance/Time

➺ u — v = 12/3

➺ u — v = 4 km/hr

Here, the pair of linear equations in two variables are :

➺ u + v = 10 . . . . . ⓵

➺ u — v = 4 . . . . . ⓶

From, ⓵ we get the value of ‘u’ as :

➺ u + v = 10

➺ u = 10 — v

Substituting this value of ‘u’ in ⓶ :

➺ u — v = 4

➺ (10 — v) — v = 4

➺ 10 — 2v = 4

➺ — 2v = 4 — 10

➺ — 2v = — 6

➺ v = — 6/— 2

➺ v = 3 km/hr

Substituting the value of ‘v’ in ⓵ :

➺ u + v = 10

➺ u + 3 = 10

➺ u = 10 — 3

➺ u = 7 km/hr

Therefore, the speed of rowing in still water is u = 7 km/hr and the speed of the current is v = 3 km/hr.

Answer 2

Answer:

u is equal to 7

v is equal to 3.

Step-by-step explanation:

hii Shreya how are you dear sis .?