Question

19 men working 15 by 2 hours a day can finish a job in 21 days how many hours a day must 45 men work to complete it in 7 days​

Answer 1

Gɪᴠᴇɴ :-

• 19 men working (15/2) hours a day can finish a job in 21 days..

Tᴏ Fɪɴᴅ :-

• How many hours a day must 45 men work to complete it in 7 days . ?

Fᴏʀᴍᴜʟᴀ ᴜsᴇᴅ :-

➺ If M1 men can do a work in D1 days working H1 hours per day and M2 men can do same work in D2 days working H2 hours per day, then

❦❦ (M1*D1*H1) = (M2*D2*H2) ❦❦

Sᴏʟᴜᴛɪᴏɴ :-

→ M1 = 19 Men

→ M2 = 45 Men

→ D1 = 21 Days.

→ D2 = 7 Days .

→ H1 = (15/2) Hours.

→ H2 = ?

Putting All values Now, we get :-

→ (19 * 21 * 15/2) = (45 * 7 * H2)

→ 19 * 3 * 15 = 45 * 2

→ 19 * 3 = 3 * 2 * H2

→ 19 = 2 * H2

→ H2 = (19/2) Hours. (Ans.)

Answer 2

Given :

• 19 men working 15 by 2 hours a day can finish a job in 21 days.

To find :

• Total Number of hours a day must 45 men work to complete it in 7 days =?

Step-by-step explanation :

Let, total numbers of hours a day = x hours.

So,

Men_1 × hours_1 × Days_1 = Men_2 × hour_2 × Days_2

So,

➮ M_1 × H_1 × D_1 = M_2 × x × D_2

Substituting the values in the above formula, we get,

19 × 15/2 × 21 = 45 × x × 17

x = 19 × 15 × 21 / 2 × 45 × 7

x = 19 × 3 / 2 × 3

x = 9.5

Therefore, Total Number of hours of a day = 9.5 hours.