Question

..UJIU 3 rupees There are almost 200 million people alive in Pakistan. If you were to distribute 100 to each Pakistani in the form of 5 rupee coin, how many moles of coins you must have? A. 6.6x10-15 C. 6.67x1014 B. 1.5x10-14 D. 1.5x1014 NUMBER​

Answer 1

Let the age of father be x years

Let the age of one of his children be y years and age of other children be z years

From given information,

x=2×(y+z)...(1)

After 20 years,

(x+20)=(y+20)+(z+20)...(2)

Substituting value of (1) in (2), we get

2×(y+z) +20=y+z+40

2y+2z−y−z=40−20

y+z=20...(3)

Substituting value of (3) in (1), we get

x=2×(20)

⇒x=40