# The boat sails along the river at a speed of 36 km / h, and against the current – at a speed of 28 km / h.

January 22, 2021 | education

| **The boat sails along the river at a speed of 36 km / h, and against the current – at a speed of 28 km / h. How long does it take for the raft to cover the distance of 24 km if it starts moving from the same point as the boat?**

Let the boat’s own speed be – X km / h, and the speed of the river flow – Y km / h.

Then, by condition:

X + Y = 36 km / h.

X – Y = 28 km / h.

Let’s solve the system of two equations by the addition method.

(X + Y) + (X – Y) = 36 + 28.

2 * X = 64.

X = 32 km / h.

Then the speed of the river is:

Y = 36 – 32 = 4 km / h.

Let us determine the time it takes for the raft to cover the distance of 24 km.

t = 24/4 = 6 hours.

Answer: in 6 hours.

One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.