Explanation

 First, he goes 12 km north

- Then 15 km east

- Then 15 km west → cancels the east movement ⇒ net horizontal displacement = 0 km

- Finally, 18 km south

Net vertical movement = 18 km south - 12 km north = 6 km south  

Explanation

Volume = (1/3)πr²h  

245π = (1/3)π×49×h  

⇒ h = (245×3)/49 = 15 cm

Explanation

81% of 6500 =  

(81/100) × 6500 = 0.81 × 6500 = 5265 kg

Explanation

"Father of my brother" refers to Abdul's father.

"Only daughter of the father" refers to Abdul's sister (since Abdul's father has only one daughter).

"He is the son of..." refers to Anwar being the son of Abdul's sister.

Therefore, Abdul is Anwar's:

Maternal Uncle

Explanation

10 ships use 10 tanks in 10 days → that means all 10 ships together use 1 tank per day.

So, 1 ship uses 1/10 of a tank per day.

Therefore, to use 1 full tank, 1 ship needs 10 days.