Five years ago, Nuri was thrice as old as Sonu. Ten years later, Nuri will be twice as old as Sonu. How old are Nuri and Sonu.

• ✦ Five years ago Nuri was thrice as old as Sonu.
• ✦ 10 years later Nuri will be twice as old as Sonu.

• ➝ present AGE of Nuri and Sonu.

LET the present age of Nuri be X years.

and, Let the present age of Sonu be y years.

Five years ago Nuri was thrice as old as Sonu.

➝ Age of Nuri = (x -5) year's

➝ Age of Sonu = (y -5) year's

According to 1st condition:-

➝ ( x -5 )= 3(y -5)

➝ (x -5) = 3y -15

➝ x - 3y = -10 .............(i)

Now,

10 years later Nuri will be twice as old as Sonu.

Age of Nuri = x+10 years

Age of Sonu = y +10 years

According to 2nd condition:-

➝ (x+10) = 2(y+10)

➝ x+10 = 2y + 20

➝ x - 2y = 10 .............(ii)

From equation (i) and (ii) , we get,

x - 3y = -10

x- 2y = 10

-- ⠀+⠀⠀--

⠀⠀-y = -20

we get, y = 20

putting value of y in equation (i)

➝ x - 3y = -10

➝ x -3×20 = -10

➝ x - 60 = -10

➝ x = 50

Hence,

Age of Nuri is x = 50 year's

Age of Sonu y = 20 year's.

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