You subtract 13,270 by 6,570 and you get 6,700 pieces of blue paper. Then, you subtract 6,700 by 2,600 and you get 4,100 pieces of yellow paper. Finally, you add the total of pieces of white, blue, and yellow paper and you get 24,070 for the total.
Sum. To build the triangle, start with 1 at the top, then continue placing numbers below it in a triangular pattern. Each number is the numbers directly above it added together.
