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 8.45% of the battery life of each mobile phone is used in a day by a typical user, which mobile phone would use a total of 1.69 hours of battery life in a day?
Phone A
Phone B
Phone C
Phone D

Using quick mental math, we can do 8% of 10 to get 0.8, which is close to the value of 0.0845*10. Also fairly quick is moving the decimal point over 1 spot to the right and we go from 0.0845 to 0.845 and that rounds to 0.8 when rounding to one decimal place. Recall that 8.45% = (8.45/100) = 0.0845

If you want to compute out the four results with a calculator, then it would look like this:

0.0845*20 = 1.69

0.0845*25 = 2.1125

0.0845*10 = 0.845

0.0845*18 = 1.521

and this shows that no other result (but choice C) is close to 0.8

So that's why the answer is choice C

Step-by-step explanation:

75 tickets have been sold so far.

step-by-step explanation:

in this question it is clearly mentioned that 45 children's tickets have been sold and this number is 60% of the total tickets sold.

now let's assume the total number of tickets sold be x.

then 60% of x = 45

⇒

⇒ x(.6) = 45

by dividing with .6 on both the sides of the equation

⇒ x = 75

therefore 75 tickets have been sold so far.

the ratio of white tiles to blue tiles is 48: 16. the ratio in it's simplest form is 3: 1.

step-by-step explanation:

ratio: take the first number and add a colon next to it, then add the second number after that. make sure the ratio order matches up with the written problem!

simplest form: we can simplify the ratio 48 : 16 by dividing both terms by the greatest common factor (gcf).

the gcf of 48 and 16 is 16.

divide both terms by 16:

48 ÷ 16 = 3

16 ÷ 16 = 1

reducing to simplest form:

48 : 16 = 3 : 1