Not Depending on the Calculator Part 1

[DyanBermeo]

My name is Dyan and I want to say that I have to become independent of the calculator for my Nursing test. If I know how to solve the problem but dont know how to do it without calculator im almost screwed. Where should I start, watch and how to practice? There is multiple choice on the test and I get extended time.

1.How do I express ratio of 15:40 as a percentage. I know that 15/40 x 100 = 37.5% How without calculator? Theres a way to reduce it to get 3/8= 37.5%

2. How do I divide this 58/1.8. How to divide decimals without calculator. Answer should be 32.22

3. What angle degree is 60% of 360 degrees. I did 360 * 60/100 which is .60 So how do you do 360 x .60 on scratch paper with no calc?

4. How do you do 250 X 40 %? I know that 250 x.40 then how do you write it out?

5. How do you divide decimals like 3.4/0.2

Please help instill this in me mind so i can not rely on calculator. Good start would be know the decimal places. Any good illustration of that please.

 

[Quaid]

I know that 15/40 x 100 = 37.5%

Oops -- we don't write a percent sign after a percentage.

15/40 = 0.375

15/40 = 37.5%

0.375 is the decimal form of 37.5%

37.5% x 100 = 37.5

0.375 x 100 = 37.5

15/40 x 100 = 37.5

The number in red is the percent; the number in blue is the percentage.

How to divide decimals without calculator

how do you do 360 x .60 on scratch paper

250 x.40 then how do you write it out

How do you divide decimals

Have you memorized the multiplication table? If not, I'd start there.

To learn how to multiply and divide decimals by hand, you could search for on-line lessons (use Google: 'multiply divide decimals without calculator').

For example, here are lessons at the Khan Academy; scroll down to the sections for multiplying and dividing decimals.

 

[HallsofIvy]

How old are you? You understand, don't you, that what you are asking is fourth or fifth grade arithmetic?