Shannon set her watch 3 seconds behind, and it falls behind another 2 seconds everyday. How many days has it been since Shannon last set her watch if the watch is 67 seconds behind

The answer is 32 all you have to do to get you answer is add 3 and 2 which gives you 5 and you add it up until you get to 67 and you have to see how many times you add it up to get the answer which is 3 or a shorter way is 31 times 2 plus 5 and it gives you 67