Adollar bill is worth pennies. when written in decimal format, each penny can be written as of a dollar. 100: 10 100: 1 100: 0.1 100: 0.01\ actually answer it correctly.

Hey there! :D

A dollar bill is worth 100 pennies. 

$1.00-> .01*100 <=== same thing

When written in decimal format, each penny can be written as 100:1, because there are 100 pennies in a dollar. One penny would just be one out of 100. 

I hope this helps!
~kaikers

A dollar bill is equal to 100 pennies. Similarly, 100 pennies is equal to a dollar.

If we want to find the value of a penny in decimal form, we must set the following equation, using the left side to represent pennies and the right side to represent dollars (this equation cannot exist, but does anyway for the sake of this question):



We want to get the left side to equal 1, so we divide both sides by the value of the left side:



Solve the fraction and turn it into a decimal:



This would mean that a penny is worth 1%, or 0.01 of a dollar.

The ratio that would fit this question is 100:0.01.

Using algebra, we can say that the first number is x, and the second number is y.

x+y=90

x-y=12

Adding these two equations gives us:

2x=102

x=51

Plugging this into the first equation,

51+y=90

y=39.

So, the two numbers are 51 and 39.