Josiah collected 15 postcards from across the United States. Then each of
his 4 grandparents gave him 7 more postcards for his collection. Which
expression could be used to find the total number of postcards he has in
his collection?
A (7+4) x 15
B (7 x 4) x 15
C (7 x 4) + 15
D (7+4) + 15
