Question

Необходимо полное решение задачи. Миша за три часа может вскопать 1/5 площади огорода, а его отец это же время 1/4 огорода. Какую часть огорода могут вскопать Миша вместе с отцом за 1 час при одновременной работе.

Answer 1

$\frac{1}{5} :3= \frac{1}{15}$часть огорода вскопает Миша за один час
$\frac{1}{4} :3= \frac{1}{12}$часть огорода вскопает отец за один час
$\frac{1}{15} + \frac{1}{12} = \frac{4+5}{60} = \frac{9}{60} = \frac{3}{20}$часть огорода вскопают вместе за один час
======================или==========
$\frac{1}{5} + \frac{1}{4} = \frac{4+5}{20} = \frac{9}{20}$часть огорода вскопают вместе за три часа
$\frac{9}{20} :3= \frac{3}{20}$часть огорода вскопают вместе за один час

Answer 2

Problem Analysis

We are given that Misha can dig 1/5 of the garden in 3 hours, and his father can dig 1/4 of the garden in the same amount of time. We need to determine what fraction of the garden they can dig together in 1 hour when working simultaneously.

Solution

To solve this problem, we can calculate the combined work rate of Misha and his father and then determine the fraction of the garden they can dig in 1 hour.

Let's start by calculating the work rate of Misha and his father individually.

Misha's work rate: 1/5 of the garden in 3 hours. Father's work rate: 1/4 of the garden in 3 hours.

To find their work rates per hour, we can divide the work done by the time taken:

Misha's work rate per hour: (1/5) / 3 = 1/15 of the garden per hour. Father's work rate per hour: (1/4) / 3 = 1/12 of the garden per hour.

Now, let's calculate their combined work rate by adding their individual work rates:

Combined work rate per hour: (1/15) + (1/12) = (4/60) + (5/60) = 9/60 = 3/20 of the garden per hour.

Therefore, Misha and his father can dig 3/20 of the garden together in 1 hour when working simultaneously.

Answer

Misha and his father can dig 3/20 of the garden together in 1 hour when working simultaneously.