Question 14
A website decided to reward the first user and every 15th user after the first user, with a free gift. How many rewards does the website give away before the 100th user visits the website?
Self-study spacing clarification (editorial): reward user 1, then add 15 to the rewarded user position each time. Count only positions strictly below 100.
Self-study spacing clarification (editorial): reward user 1, then add 15 to the rewarded user position each time. Count only positions strictly below 100.