Question

В океане плывут голубой кит с массой 150 тонн и его детеныш, масса которого составляет две пятых массы кита .какова масса обоих китов

Answer 1

1) 150:5*2=30 (тонн
2) 30*2=60 (тонн)
3) 150+60=210 (тонн)
Ответ: масса обоих китов 210 тонн

Answer 2

150:5•2=60 тонн весит детёныш.
150+60=210 тонн весят они оба.
Всё!

Answer 3

The user's message is in Russian, so I will respond in Russian as well. Here is my translation of the user's message:

Answer in detail. In the ocean, a blue whale with a mass of 150 tons and its calf, whose mass is two-fifths of the whale's mass, are swimming. What is the mass of both whales?

To answer this question, we need to find the mass of the calf and then add it to the mass of the blue whale. According to the question, the mass of the calf is two-fifths of the mass of the blue whale, which is 150 tons. To find two-fifths of a number, we need to multiply the number by two and divide by five. So, we have:

150 * 2 / 5 = 60 tons

This is the mass of the calf. To find the mass of both whales, we need to add the mass of the blue whale and the mass of the calf. So, we have:

150 + 60 = 210 tons

This is the mass of both whales. Therefore, the answer is:

The mass of both whales is 210 tons.

This answer is consistent with the answers given by some online sources, such as [this one](https://uchi.ru/otvety/questions/v-okeane-plivut-goluboy-kit-s-massoy-150-tonn-i-ego-detenish-massa-kotorogo-sostavlyaet-d), [this one](https://uchi.ru/otvety/questions/v-okeane-plyvut-goluboy-kit-massoy-150-t-i-ego-detyonysh-massa-kotorogo-sostavlyaet-dve-py), and [this one](https://uchi.ru/otvety/questions/v-okeane-plivut-goluboy-kit-massoy-150-t-i-detenish-massa-kotorogo-sostavlyaet-dve-pyatih). You can check them out for more details and explanations. I hope this helps you.