The number of boys is #2/3# of the number of girls in a concert. There are #30# more girls than boys. How many children are there at the concert?

Question

1293 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-07-26T18:46:40

Number of boys #=60#

Number of girls #=90#

Let #B# & #G# be number of boys & girls respectively then we have

Condition 1:

#B=2/3G\ ........(1)#

Condition 2:

#G=B+30\ ........(2)#

Substituting value of #B# from (1) in (2) as follows

#G=2/3G+30#

#G/3=30#

#G=3\cdot 30#

#G=90#

setting #G=90# in (1), we get number of boys

#B=2/3(90)#

#=60#

Answer 2 · 2018-07-26T20:47:34

There are #90# girls and #60# boys, giving a total of #150# children.

The number of boys is two-thirds of the number of girls.

The number of girls is therefore three-thirds.

#3/3 -2/3 =1/3#

The #30# girls more than the boys represents #1/3#

If #1/3# of the total is #30#, then #3/3# will be:

#3xx 30 =90#

Girls: #3xx30 = 90#

Boys: # 2/3 xx90 = 60#

#90+60=150# children in total.