Sara is researching phones and decides to create a weighted average to determine the ‘best’. She uses the following weights: 50% battery life, 30% cost, 20% camera to calculate a ‘score’ for each phone. She finds the following ratings out of 10 for each category on the internet.
Battery Cost Camera
iPhone 9 7 8
Samsung 9 7 7
Motorola 8 9 8
Calculate the weighted average ‘score’ for each phone.
(round to the tenths place)
I will give you a start.
iPhone = .5(9) + .3(7) + .2(8) = ?
8.2
Sure, let's calculate the weighted average score for each phone:
For the iPhone:
Weighted Average Score = (50% x Battery) + (30% x Cost) + (20% x Camera)
= (50% x 9) + (30% x 7) + (20% x 8)
= 4.5 + 2.1 + 1.6
= 8.2
For the Samsung:
Weighted Average Score = (50% x Battery) + (30% x Cost) + (20% x Camera)
= (50% x 9) + (30% x 7) + (20% x 7)
= 4.5 + 2.1 + 1.4
= 8.0
For the Motorola:
Weighted Average Score = (50% x Battery) + (30% x Cost) + (20% x Camera)
= (50% x 8) + (30% x 9) + (20% x 8)
= 4.0 + 2.7 + 1.6
= 8.3
Therefore, the weighted average 'score' for each phone is as follows:
- iPhone: 8.2
- Samsung: 8.0
- Motorola: 8.3
To calculate the weighted average score for each phone, we will multiply each category rating by its corresponding weight, and then sum the weighted scores.
For the iPhone:
Weighted Battery score = 9 * 0.5 = 4.5
Weighted Cost score = 7 * 0.3 = 2.1
Weighted Camera score = 8 * 0.2 = 1.6
Weighted average score = 4.5 + 2.1 + 1.6 = 8.2
For the Samsung:
Weighted Battery score = 9 * 0.5 = 4.5
Weighted Cost score = 7 * 0.3 = 2.1
Weighted Camera score = 7 * 0.2 = 1.4
Weighted average score = 4.5 + 2.1 + 1.4 = 8.0
For the Motorola:
Weighted Battery score = 8 * 0.5 = 4.0
Weighted Cost score = 9 * 0.3 = 2.7
Weighted Camera score = 8 * 0.2 = 1.6
Weighted average score = 4.0 + 2.7 + 1.6 = 8.3
Therefore, the weighted average score for each phone is as follows:
- iPhone: 8.2
- Samsung: 8.0
- Motorola: 8.3
To calculate the weighted average score for each phone, we will multiply the rating of each category (battery life, cost, and camera) by their respective weights and then sum up the results.
For the iPhone:
Weighted score for battery life = 9 * 0.5 = 4.5
Weighted score for cost = 7 * 0.3 = 2.1
Weighted score for camera = 8 * 0.2 = 1.6
Weighted average score for the iPhone = 4.5 + 2.1 + 1.6 = 8.2
For the Samsung:
Weighted score for battery life = 9 * 0.5 = 4.5
Weighted score for cost = 7 * 0.3 = 2.1
Weighted score for camera = 7 * 0.2 = 1.4
Weighted average score for the Samsung = 4.5 + 2.1 + 1.4 = 8.0
For the Motorola:
Weighted score for battery life = 8 * 0.5 = 4.0
Weighted score for cost = 9 * 0.3 = 2.7
Weighted score for camera = 8 * 0.2 = 1.6
Weighted average score for the Motorola = 4.0 + 2.7 + 1.6 = 8.3
Therefore, the weighted average scores for each phone are as follows:
- iPhone: 8.2
- Samsung: 8.0
- Motorola: 8.3