Question

rakhi's mother is four times as old as rakhi. after 5 years her mother will be three times as old as will be then find their present ages.

Answer 1

PRESENT AGES
Let the present age of Rakhi be $x$ years. 
Present age of Rakhi's mother is $4x$ years. 

AFTER 5 YEARS
Age of Rakhi = $(x+5)$ years
Age of Rakhi's mother = $(4x+5)$ years

SOLVING YOUR QUESTION
ATQ (According To Question)
$(4x+5) = 3(x+5)$     [Solve for $x$ in the equation. ]
$4x+5 = 3x+15$
$4x-3x = 15-5$     [Transposing 3x to LHS and 5 to RHS. ]
$x = 10$

FINDING THEIR PRESENT AGES
Present age of Rakhi = $x$ years = 10 years
Present age of Rakhi's mother = $4x$ years = (4×10) years = 40 years

∴ The present age of Rakhi is 10 years and that of her mother is 40 years. 

Hope this may help you. 

Answer 2

Hope it helps you........