Question

PROBLEM SOLVING- The number of left-handed people in the world is one-tenth the number of right-handed people. The percent of right-handed people is nine times the percent of left-handed people and ambidextrous people combined. What percent of people are ambidextrous?

Answer 1

Answer: There are 1% of people are ambidextrous.

Explanation:

Let the number of percent of left handed people be 'x'.

Let the number of percent of right handed people be 'y'.

Let the number of percent of ambidextrous people be 'z'.

According to question, the number of left handed people in the world is one tenth the number of right handed people.

so, it becomes,

`x=(y)/(10)\\\\10x=y`

The percent of right handed people is nine times the percent of left handed people and ambidextrous people combined.

`(y)/(100)=9((x)/(100)+(z)/(100))\\\\y=9x+9z`

So, from both the equations we get that

`10x=9x+9z\\\\10x-9x=9z\\\\x=9z`

As we know that

`x+y+z=100\\\\x+10x+(x)/(9)=100\\\\11x+(x)/(9)=100\\\\(99x+x)/(9)=100\\\\(100x)/(9)=100\\\\x=9`

So, percent of people are ambidextrous is given by

`x=9z\\\\9=9z\\\\(9)/(9)=z\\\\z=1\%`

Hence, there are 1% of people are ambidextrous.