Please answer these two questions: 1. If 1/4 yard of string is needed for an art project, how much string will remain from a piece that measures 7/8 yard? 2. There are two different sizes of tiles to choose from. One tile is 1/4 inch thick, and the other is 7/12 inches thick. What is the combined thickness of the two tiles?

1: If you have 7/8 yard of string and you need 1/4 yard for an art project, you would do the following subtraction to find out how much string will remain:

7/8 yard (initial length of string) - 1/4 yard (amount needed for the project) = remaining string.

First, we need to make sure our fractions have a common denominator before we can subtract them. The least common denominator for 8 and 4 is 8. So we need to convert 1/4 yard to a fraction with the denominator of 8:

1/4 yard = 2/8 yard (since 1x2 = 2 and 4x2 = 8 to get an equivalent fraction).

Now, we can subtract:

7/8 yard - 2/8 yard = (7 - 2)/8 yard = 5/8 yard.

So, 5/8 yard of string will remain after using 1/4 yard for the art project.

2: To find the combined thickness of the two different tiles, one which is 1/4 inch thick and the other which is 7/12 inches thick, you simply need to add the fractions:

1/4 inch + 7/12 inch.

First, find a common denominator, which is 12 in this case, to be able to add the fractions together. The fraction 1/4 needs to be converted to have a denominator of 12:

1/4 inch = 3/12 inch (since 1x3 = 3 and 4x3 = 12 for an equivalent fraction).

So now we can add:

3/12 inch + 7/12 inch = (3 + 7)/12 inch = 10/12 inch.

The fraction 10/12 can be simplified by dividing both numerator and denominator by their greatest common divisor, which is 2:

10/12 inch = (10÷2) / (12÷2) = 5/6 inch.

Therefore, when you combine the two tiles, the total thickness will be 5/6 inch.