Question

if 10 men working 7 hours a day dig a trench 147 m long how many men working 8 hours a day will dig a trench 168 metre long (of the breadth and depth the first in the same number off days)?​

Answer 1

Answer:

12 men working

Step-by-step explanation:

no step emplanation

Answer 2

★Given:-

• 10 men working 7 hours a day dig a trench 147 m long.

★To find:-

• How many men working 8 hours a day will dig a trench 168 metre long (of the breadth and depth the first in the same number off days)?​

★Solution:-

Let,

• No of days taken to dig a 147m long trench = x

→No of hours they worked = 7 × x hrs

→10 men worked for  7 × x hrs = 147m

→10 men working for 1 hr =  147/7x m

→1 men working for  1 hr = 147/(7×10× x)m

Let,

• No of days taken to dig a 168m long trench = y

→y men working for 1 hr =  y(147/(7×10×x)) m.

→y men working for 8× x hrs = y(147/(7×10×x))(8×x) m.

⇒y(147×8/(7×10) = 168

⇒y = 168×7×10/(147×8)

⇒y = 21×7×10/147

⇒y = 10

Hence,

10 men working 8 hrs a day will dig a trench 168 m long.

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