In May, there are 31 days. If Elizabeth is taking the daily recommendation, she will be taking 29,512 milligrams f vitamin D. In a gram, there are 1000 milligrams. Therefore, you need to divide 29,512 by 10000. 29,512/1000= 29.512 Thus, Elizabeth has taken 29.512 GRAMS of Vitamin D in May. Hope this helps :)
If the mean of four numbers is 7, we know that their sum is 7 * 4 = 28. We can use this information to find the last number. If the fourth number is x, we can write:
