An adult has 206 bones. Of those, approximately 2.9% are found in the inner ear. About how many bones in the human body are found in the inner ear?

1 Answer
May 14, 2016

6 bones

Explanation:

The two steps to solving this problem are:

1. Converting 2.9% into a fraction.
2. Multiplying the fraction form of 2.9% by the total number of bones in the human body.

Rewriting 2.9% as a Fraction
Since % means "out of hundred," put 2.9 over 100.

2.9%

=2.9/100

As there cannot be any decimals in a fraction, you must get rid of the decimal. You do this by multiplying the numerator and denominator by 10.

=2.9/100(10/10)

=29/1000

Determining the Number of Bones Found in the Inner Ear
Multiply 206 bones by 29/1000.

206color(white)(i)"bones"*29/1000

Since 206 and 1000 can be divided by a common factor of 2, their values are reduced.

=206color(red)(-:2)color(white)(i)"bones"*29/(1000color(red)(-:2))

=103color(white)(i)"bones"*29/500

Solve.

=5.974color(white)(i)"bones"

~~color(green)(|bar(ul(color(white)(a/a)color(black)(6color(white)(i)"bones")color(white)(a/a)|)))