Anna, Boris, and Clara thought of 1 number each Ana's number increased by 20 is 21 greater than boris's number decreased by 22. Boris's number decreased by 20 is 21 greater than claras number increased by 22. How much less is claras number than annas number?

Clara's number is 42 less than Anna's number

Step-by-step explanation:

We can start this problem out by setting our variables up:

A= Anna's number

B= Boris's number

C= Clara's number

so we can use them to build our equations. We can sepparate the problem into little more understandable pieces of information, let's start with the first piece of information:

- "Ana's number increased by 20"

A+20

- "boris's number decreased by 22"

B-22

- "21 greater than boris's number decreased by 22."

(B-22)+21

- "Ana's number increased by 20 is 21 greater than boris's number decreased by 22."

A+20=(B-22)+21

This is our first important equation here. Let's go with the second part of the problem:

- "Boris's number decreased by 20"

B-20

- "claras number increased by 22"

C+22

- "21 greater than claras number increased by 22"

(C+22)+21

Now the whole thing:

"Boris's number decreased by 20 is 21 greater than claras number increased by 22."

B-20=(C+22)+21

This is our second important equation.

So now we have the following system of equations:

A+20=(B-22)+21

B-20=(C+22)+21

We can now simplify the equations by combining like terms so we get:

Equation 1:

A+20=(B-22)+21

we can get rid of the parenthesis so we get:

A+20=B-22+21

We can subtract a 20 from both sides of the equation so we get:

A=B-22+21-20

We perform the subtractions so we get:

A=B-21

Equation 2:

B-20=(C+22)+21

We get rid of the parenthesis:

B-20=C+22+21

We add a 20 to both sides so we get:

B=C+22+21+20

We can now perform the additions so we get:

B=C+63

And now we can combine the equations. In this case we can substitute equation 2 into equation 1 to get:

A=C+63-21

We combine like terms to get:

A=C+42

We can subtract 42 from both sides to get:

C=A-42

which reads:

Clara's number is 42 less than Anna's number.

40 minutes

step-by-step explanation:

add the time and multiply by 2