Question

The table shows the battery life of four different mobile phones.


Mobile Phone Battery Life
Phone Battery Life
(hours)
A 20
B 25
C 10
D 18


If 6.45% of the battery life of each mobile phone is used in a day by a typical user, for which mobile phone is 1.6125 hours of battery life used in a day?
Phone A
Phone B
Phone C
Phone D

Answer 1

@mayankdevnani:

Answer 2

any ideas?

Answer 3

Hint:- let x be the battery life of the phone

Answer 4

ok... still not getting it tho

Answer 5

well 6.45% of this battery life = how many hours?

Answer 6

1?

Answer 7

Check the second part of the question

Answer 8

still not understanding

Answer 9

im not sure but im guessing the answer is b not sure if im right tho

Answer 10

Part of being able to answer a word problem is to read the problem carefully and understand the question. Even if at first you may not know how to answer the question, you should be able to understand what the question is. Read the question carefully and get a good understanding of what the given information is and what you are asked to find.

Answer 11

Don't guess.
You have a 1 out of 4 chance of being correct.
Since this is a problem involving percentages, if you guess you have just a 25% chance of being correct.
Let's work it out together.

Answer 12

ok

Answer 13

There are 4 battery lives given:
20 hours, 25 hours, 10 hours, 18 hours.

Now look at the info you are given and the question.

Answer 14

ok

Answer 15

A typical person uses 6.45% of the phone battery life in 1 day.
Someone used the typical 6.45% of his battery life by using the phone 1.6125 hours.
Which battery is it?

The problem is asking you this question:
6.45% of what number of hours is 1.6125 hours?

Answer 16

25

Answer 17

Now we translate the question into a math equation and we solve it.
In algebra, we use variables (usually letters) to represent unknown amounts.
Let the total amount of battery life be x.

6.45% of x = 1.6125

0.645x = 1.6125

Divide both sides by 0.645 to get

x = 25

The answer is 25 hours, or choice B.

Answer 18

You are correct, but now it's not a guess.

Answer 19

so i was right
yasssssss thank you

Answer 20

You're welcome.