Explanation

Given:

• Length of each train = 150 m

• Total length to cross = 150 m + 150 m = 300 m

• Time taken to cross = 15 seconds

• Trains are moving in opposite directions at the same speed

 Step 1: Use the formula

Relative speed= Total distance/Time ​= 300 / 15​ = 20 m/s

Since both trains have the same speed and are moving in opposite directions:

Relative speed=v+v=2v=20 m/s⇒v=20​/2=10 m/s

Step 2: Convert to km/h

$$1 text{m/s} = 3.6 text{km/h} Rightarrow 10 text{m/s} = 10 times 3.6 = 36 text{km/h}$$

Explanation

A car travels 120 km in 2 hours

Then the distance traveled by the car in 1 hour = 120/2km 

=60km

Then the distance travelled by the car in 3 hours= 3*60km

=180km

Hence the car travels 180km in 3 hours

Explanation

Abid said: MOre than 10 km but less than 15 km

Resham knew: More than 12 km but less than 14 km 

13 km is common in both statement

Explanation

Leap year : 1980, 1984, 1988, 1992, ____

The normal Year is 365 days 

leap year is 366 days 

so, 

Saturday on 17th December 1982 

Sunday on 17th December 1983

Tuesday on 17th Dec 1984

What will be on 22nd Dec 1984

Wednesday on 18th Dec 1984

Thursday on 19th 

Friday on 20th 

Saturday on 21st 

Sunday on 22nd

Explanation

Sabir's brother's birthday is the 16th and 17th of Feb 

Rabia's brother's birthday is the 17th and the 18th Feb 17th is common in both birthday

Explanation

Let the required number of labourers be x

Less working hour/day, More labours (Indirect proportion)

More days, fewer labourers (Indirect proportion)

Explanation

w = Men x Days x Hours 

12 x 8 x 10 = 960

 960 / 8 x 15 = 8 Men

Explanation

LCM of 1/10 + 1/40 = 1/8

Number of days to complete the total work = 8 days

Explanation

Explanation

ایک لیٹر میں کتنا کرتی ہے

150/20 = 7.5

 تین سو بیس لیٹر میں کتنا کرے گی

320/7.5 = 42.67