30 + -30 = 0 a. Complete the sum so that the two numbers equal O.
+ 589
b. Complete the sum so that the three numbers equal O.
-589
- 89
c. Complete the sum so that the four numbers equal O and none of the numbers are opposites,
-589+
- 90 + (-1)
(Lesson 5-3)

1

Step-by-step explanation:

Probability of drawing a black ball is:

3/ 12= 0.25

Probability of drawing a red ball is:

5/12= [total number of red balls/ total number of balls]

Probability of drawing a white ball is:

4/12= 1/3 [total number of white balls/ total number of balls]

In probability, 'or' means 'sum'

So we sum them all;

We get: 5/12 + 3/12 + 4/12 =1