Marco is making three tiles pictures. he uses 310 green tiles to make each picture. he uses 50 fewer red tiles than green tiles for each picture. how many red and green tiles does he use in all?

Hi there!

To solve this problem, we need to first find the amount of red tiles he used by subtracting 50 from 310, and then finding the sum of the two numbers. 

310 - 50 = 260

Now, we know that there are 260 red tiles.

3 * 310 = 930
3 * 260 = 780

930 + 780 = 1710

So, the answer is 1710 tiles total. 

Hope this helps!

The correct one is c.