Of three numbers, two are ½ and ⅓. what should the third number be so that the average number of all three is 1.

If there were 3 numbers, and the average is 1, they would all add up to 3. 1/2 + 1/3 = 5/6. 3 - 5/6 = 2 1/6. The third number should be 2 1/6.

5

step-by-step explanation:

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.