One day in the playground,the ratio of the number of boy to the number of girl is 3:5 later 6girls come, 9boy leave, the ratio of the number

Question

One day in the playground,the ratio of the number of boy to the number of girl is 3:5 later 6girls come, 9boy leave, the ratio of the number of girl become 1:4. Find the difference between the number of boy and girl originally

in progress 0
Gerda 4 years 2021-08-14T15:56:26+00:00 1 Answers 13 views 0

Answers ( )

  1. Tryphena
    0
    2021-08-14T15:58:19+00:00
    Reply

    Answer:

    The number of boys are 18 and the number of girls are 30.

    Step-by-step explanation:

    The ratio of number of girls to the boys = 3 : 5

    Let the number of girls is g and boys is b initially.

    b : g = 3 : 5

    5 b = 3 g ….. (1)

    Now, girls are 6 + g and boys are b – 9

    So, the ratio is

    (b – 9) : (6 + g) = 1 : 4

    4 b – 36 = 6 + g

    4 b – g = 42 …. (2)

    From ( 1 ) and ( 2 )

    4 b - \frac {5 b}{3}= 42\\\\\frac{7 b }{3} = 42\\\\b = 18

    And , g = 5 x 18/3 = 30

    So, the number of boys are 18 and the number of girls are 30.  

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )