How to add odd numbers - ACT Math
Card 0 of 4
Solve: 
Solve:
Add the ones digits:
Since there is no tens digit to carry over, proceed to add the tens digits:
The answer is 
.
Add the ones digits:
Since there is no tens digit to carry over, proceed to add the tens digits:
The answer is
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At a certain high school, everyone must take either Latin or Greek. There are 
more students taking Latin than there are students taking Greek. If there are 
students taking Greek, how many total students are there?
At a certain high school, everyone must take either Latin or Greek. There are
If there are 
students taking Greek, then there are 
or 
students taking Latin. However, the question asks how many total students there are in the school, so you must add these two values together to get:
or 
total students.
If there are
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Find the sum of 13 and 19.
Find the sum of 13 and 19.
Rewrite the question in a mathematical expression.
Add the ones digit.
Since this number is larger than 
, carry over the 
in tens digit when adding the next term.
Add the tens digit with the carry over.
Combine the tens digit and the ones digit. The answer is 
.
Rewrite the question in a mathematical expression.
Add the ones digit.
Since this number is larger than
Add the tens digit with the carry over.
Combine the tens digit and the ones digit. The answer is
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In order to get an odd result from an addition, we must have one odd and one even number, thus you know from the first point about 
that only one of the two values is odd. Now, to get an even result, you can have two evens or two odds. So, let's presume that 
has two odd values, this means that 
must be even. Thus, you have:
Now, if we presume that 
has two even values, we must then know that 
is odd. Thus, we have:
First of all, you can eliminate the two answers that say that a given value is positive or negative. This cannot be told from our data. Next, it cannot be the case that 
is even. It will always be odd (hence, the correct answer is this). Finally, it cannot be that 
is even always. In the second case above, you will have two even numbers added together, given you an even. Then, you will add in an odd, giving you an odd.
In order to get an odd result from an addition, we must have one odd and one even number, thus you know from the first point about
Now, if we presume that
First of all, you can eliminate the two answers that say that a given value is positive or negative. This cannot be told from our data. Next, it cannot be the case that
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