A jar contains blue and green marbles The number of green marbles is 5 more than twice the number of blue if probability of drawing a blue one at random is 2/7 , how many blue and green marbles are there in the jar

let the no. of blue marbles be x

.'. the no. of green marbles = 2x + 5

.'. the total no. of marbles = 2x + 5 + x = 3x + 5

then, the probability of drawing blue marble =   x /  3x + 5 = 2/7

On further solving we get, 7x = 6x + 10

.'.                                            7x - 6x = 10

                                         =>          x = 10

So, the no. of blue marbles = 10

according to the equation 2x + 5, the no. of green marbles = 2* 10 + 5

                                                                                                       => 20 + 5 = 25

hope this will be helpful for u