Answer:
6 candy tarts
Explanation:
Based on Leila's observations, we would expect all boxes of candy tarts to have 1/7 grape-flavoured ones. If we have a box of 40, we can find the expected number of grape flavoured nady tarts by multiplying 40 and 1/7.
40 × 1/7 = 5.714285714
You can round this to 6 candy tarts