My first thought when I read this problem was "11 is a factor of 1155." Indeed, 1155 equals 11 times 105. Next, determine factors of 105. I see that 5 is a divisor of both 10 and 5, so that 105 equals 5 times 21.
Adding together these three integers: 11+5+21 = 37
But wait! 21 can be factored (e. g., into 7 times 3).
You'll need to identify all of the several sets of 3 positive integers each and find the sum of each set. Only after you've done this can you choose the set whose sum of the three integers is the smallest. Please show your work, so that others can give you feedback on it.
a rectangle has four sides, two pairs of identical sides. So two sides are 16. So that adds up to 32. Perimeter is all sides added together. so it has to add up to 72. 72 minus 32 is 40, so two of the sides have to be 40. Area is length times width, so 16 times 20, which is 320.
