Question

Три друга за час літніх канікул розв'язали разом 320 задач. Перший розв'язав 45% всіх задач, другий - 35% всіх задач, а третій - розв'язав решту. Скільки задач розв'язав третій друг пiд час літніх канікул?​

Answer 1

Ответ:

20%=64 задачі

Пошаговое объяснение:

Якщо 320 задач це 100%,перший хлопець розв'язав 45%,другий 35%,то третій 100-(45+35)=20%

Тобто,перший розв'язав 45% задач,45% від 320 це виходить 144 задачі розв'язав перший хлопець, другий 35% всіх задач це 112 задач, тож третій 320-(144+112)=64 задачі розв'язав третій.

Answer 2

Problem Analysis

We are given that three friends solved a total of 320 problems during their summer vacation. The first friend solved 45% of all the problems, the second friend solved 35% of all the problems, and the third friend solved the rest. We need to determine how many problems the third friend solved.

Solution

To find the number of problems solved by the third friend, we first need to calculate the number of problems solved by the first and second friends.

Let's start by finding the number of problems solved by the first friend. We know that the first friend solved 45% of all the problems. To calculate this, we can multiply 45% by the total number of problems:

Number of problems solved by the first friend = 45% of 320

Next, let's find the number of problems solved by the second friend. We know that the second friend solved 35% of all the problems. Using the same approach as before, we can calculate this:

Number of problems solved by the second friend = 35% of 320

Finally, to find the number of problems solved by the third friend, we subtract the sum of the problems solved by the first and second friends from the total number of problems:

Number of problems solved by the third friend = Total number of problems - (Number of problems solved by the first friend + Number of problems solved by the second friend)

Let's calculate the values step by step:

1. Number of problems solved by the first friend: - 45% of 320 = (45/100) * 320 = 144

2. Number of problems solved by the second friend: - 35% of 320 = (35/100) * 320 = 112

3. Number of problems solved by the third friend: - Total number of problems - (Number of problems solved by the first friend + Number of problems solved by the second friend) - 320 - (144 + 112) = 320 - 256 = 64

Therefore, the third friend solved 64 problems during the summer vacation.

Answer

The third friend solved a total of 64 problems during the summer vacation.