Which explanation best describes how to solve this problem?
gloria was taking photographs at a waterfall. she deleted 18 photographs. then, during the hike from the waterfall, she took 13 more. she deleted another 9. now gloria has 22 photographs left. how many photographs did gloria have to begin with?
a. guess and test. guess that gloria had 40 photographs to begin with. subtract the number she deleted (18) and add the number she took (13). then subtract the second amount she deleted (9). this gives 26. that is 4 more than 22. add 4 to your guess. gloria had 44 photographs to begin with.
b. draw a diagram. draw a large circle to represent the photographs gloria had to begin with. add 22 dots, 18 dots, and 9 dots to the circle. cross out 13 dots for the ones she took during the hike. add all remaining dots to figure out that gloria started with 36 photographs.
c. translate into an equation. 18 + 13 + 9 – 22 = b
gloria had 18 photographs to begin with.
d. work backward. start with the number of photographs that gloria has left (22). add the photographs that were deleted (18 + 9). then add photographs that she took during the hike (13).
gloria had 62 photographs to begin with.