Question

What's the answer to this math problem

Answer 1

Total number of marbles:
75 + 50 + 100 + 25 = 250

Probability of selecting a red marble:
25/250 (since 25 out of 250 marbles are red)
Since the top and bottom of this fraction are both divisible by 25, we can go ahead and divide them both by 25, simplifying to 1/10.

Probability of selecting a green marble:
50/250
Simplifies to 2/10
Simplifies to 1/5.

Probability of selecting a blue or orange marble
(75+100)/250
175/250
Simplifies to 7/10.

To find the probability that each event occurs in order, simply multiply them all together.

$\frac{1}{10}\times\frac{1}{5}\times\frac{7}{10}=\frac{1\times1\times7}{10\times5\times10}=\boxed{\frac{7}{500}}$

Answer 2

Answer:

7/500 or Answer Choice B

Step-by-step explanation:

1. First find the total # of ALL the marbles in the bag. (75 + 50 + 100 + 25 = 250)

2. Then define the percentage of each marble color in said bag.

• blue: 75 out of 250 (75/250) = 30%
• green: 50 out of 250 (50/250) = 20%
• orange: 100 out of 250 (100/250) = 40%
• red: 25 out of 250 (25/250) = 10%

3. Double check that the percentage = 100. (yes)

4. Understand that she could pick the said marble colors not in the order that was specified, so to determine the chances of picking the right colors in the right order. Multiple the values.

red marble: 1/10 chance

green marble: 2/10 or 1/5 chance

blue OR orange (this means add together and then divide by total: 250): 7/10 chance

multiply fractions: 1/10 x 1/5 x 7/10 = 7/500 (this is simplified)

5. Select Answer Choice (B)