What is 12 8/15-7+7/15+15? Simplify your answer

A. 20 15/15
B. 41 15/15
C. 35
D. 21

To simplify the expression, we can first convert the mixed number 12 8/15 into an improper fraction.

12 8/15 can be written as (12 * 15 + 8)/15, which equals 188/15.

Now we can substitute the values back into the expression:

188/15 - 7 + 7/15 + 15

To add or subtract fractions, we need to have a common denominator. In this case, the denominator is already the same, so we can combine the numerators:

(188 - 105 + 7 + 225)/15

Now we can simplify the numerator:

(188 - 105 + 7 + 225)/15 = 315/15

Dividing the numerator and denominator by their greatest common factor, which is 15, we get:

21/1

So the answer is 21.

Therefore, the correct option is D. 21.

What should you do if a place value is missing a number?

A. Remove the last digit(s) in the number that has the additional place values
B. Add a zero.
C. Subtract without it.
D. Nothing.

B. Add a zero.

If a place value is missing a number, we can add a zero in that place value to indicate that it holds a value of zero. This helps maintain the correct positional value of digits within a number.

To simplify the expression 12 8/15 - 7 + 7/15 + 15, we can start by converting the mixed numbers into improper fractions.

12 8/15 can be written as (12*15 + 8)/15 = (180 + 8)/15 = 188/15.

Combining like terms, we have 188/15 - 7 + 7/15 + 15.

Next, we need to find a common denominator for the fractions. The common denominator of 15 and 1 is 15.

Rewriting the expression with a common denominator, we get (188 - 7*15 + 7)/15 + 15.

Now, we can simplify the expression further.

Multiplying 7 * 15 gives us 105.

The expression becomes (188 - 105 + 7)/15 + 15.

Simplifying the numerator gives us (83 + 7)/15 + 15.

Adding 83 + 7 gives us 90.

The expression becomes 90/15 + 15.

Simplifying 90/15 gives us 6.

The final expression is 6 + 15.

Adding 6 and 15 gives us 21.

Therefore, the answer is D. 21.