Answer:
(4+5)+(3+3) because you have eto break up the numbers
The answer is 7.5 liters that should of evaporated
In 371 ways Mrs. Sullivan choose two students from 27 to help put away calculators at the end of class
Step-by-step explanation:
let us assume that Mrs.Sullivan wants to choose 2 students from a group of 27 students
So ,in the first choice we have 27 students
In the second choice we have 26 choices
So Mrs.Sullivan has = 27 × 26 = 702 ways
But each group repeated twice,in order to avoid that we will divide the answer by 2
so we will write
= 702 ÷ 2 =<u> 351 ways</u>
<u>This method of calculation is called Combination</u>