Question

Толя может вскопать огород за 12 часов. Толя с Колей вместе могут вскопать огород за 9 часов. За какое время огород может вскопать один Коля?​

Answer 1

Пошаговое объяснение:

13-9=3

9-3=6

ответ: 6 часов

Answer 2

To solve this problem, we can use the concept of "work rate" or "productivity." Work rate is the amount of work done per unit of time. Let's say the amount of work to be done (vskopat' ogorod) is represented as "W."

Let T be the time it takes for Kolya to dig the garden alone (in hours).

Given information:

1. Tolya's work rate: 1 garden per 12 hours (1 garden/12 hours).
2. Tolya and Kolya together work rate: 1 garden per 9 hours (1 garden/9 hours).

Now, let's set up equations based on the work rate:

1. Work rate of Tolya and Kolya together: (Tolya's rate) + (Kolya's rate) = Combined rate 1/12 + 1/T = 1/9

2. Work rate of Tolya and Kolya together is the same as Kolya's work rate when he works alone: 1/9 = 1/T

Now, let's solve for T (the time it takes for Kolya to dig the garden alone):

1/T = 1/9 T = 9 hours

So, Kolya can dig the garden alone in 9 hours.