Four children have small toys. The first child has 1/10 of the toys, the second child has

12 more toys than the first, the third child has one more toy of what the first child has

and the fourth child has double the third child. How many toys are there?

Verified Answer :

a,b,c,d
x=number of toys total
a+b+c+d=x
a=(1/10)x
b=12+(1/10)x
c=1+(1/10)x
d=2(1+(1/10)x)=2+(2/10)x
add them

(1/10)x+12+(1/10)x+1+(1/10)x+2+(2/10)x=x
group like terms
(1/10)x)+(1/10)x+(1/10)x+(2/10)x+12+1+2=x
add like terms
(5/10)x+15=x
(1/2)x+15=x
subtract (1/2)x from both sides
15=(1/2)x
multily both sides by 2/1 to clear fraction
30=x

30 total toys