significant figures?

Question

Does anyone have any info out there on how to work multiplication, division, addition and subtraction on sig figs? and A LOT of examples. thanks!

Answer 1

TO MULTIPLY
• Any even number by 5 :divide by 2 the number you are multiplying by 5 and place a zero after the number (append a zero)
8792 * 5 = ? ==> divide the number by 2 ==> 8792/2= 4396 ==> append a zero ==> 43960
• Any odd number by 5 :subtract one from the number you are multiplying, then halve that number and place a 5 after the resulting number.
4157*5 = ? ==> substract one from the number ==> 4157-1=4156 ==> halve the number ==> 4156/2=2078 ==> append a 5 ==> 20785
• Any number by 4: double the number and then double it again.
35*4 = ? ==> double the number ==> 35+35 or 35*2 = 70 ===> double it again ==>70 * 2 or 70 + 70 ==> 340
• Any number by any number of 9's: append as many 0's to the multiplicand as there 9's in the multiplier , and from this number subtract the multiplicand
484 * 999 = ? ==> append as may 0's to the multiplicand ==> 484 000 ==> substract the multiplicand ==> 484000 - 484 = 483516
• Any number by 10: just add a 0 behind the number (append a zero)
894756209*10= ? ==> write down the number ==> 894756209 ==> append a 0 ==> 8947562090
• Any number by 11: working from right to left: write down the first number, then add each number to the previous number and write it down, when added together if the sum is more than 9 then you carry over, do this until you have work with all the numbers.
963157*11= ? ==> write down the first number from right to left ==> _ _ _ _ _ 7 ==>add 7 to the previos number, carry on if exist ==> 7+5 =12 carry 1 write 2 ==> _ _ _ _ 2 7 ==>add 5 to the previos number plus the carry on if exist ==> 5+1= 6 , 6 + 1(carry on) = 7 write 7 ==> _ _ _ 7 2 7==> 1+3 = 4, write 4 ==> _ _ 4 7 2 7 ==> 3 + 6 = 9, write 9 ==> _ 9 4 7 2 7 ==> 6 + 9 = 15, write 5 and carry on 1 ==> _ 5 9 4 7 2 7 ==> 9+0 = 9 + 1 (carry on) = 10, write 10 ==> 1 0 5 9 4 7 2 7
• Any number by 15: multiply the number by 10 and multiply the number by 5, add those numbers:
5846*15 ===> multiply the number by 10 ==> 5846 0 (remember append 0) ===> multiply the number by 5 ==> divide by 2 5846/2 = 2923 and append 0 , 29230 ===> add the numbers ==> 58460+29230 = 87690 (This help to calculate a 15% tip)
• 1 and Any number of 0's (10, 100, 1000, 10000....): just add as many 0's you have to the number .
5743653*100000 = ? ==> write the number ==> 5743653 ==> append as many 0's you have ==> 574365300000

TO SQUARE:
• A 2 digit number ending in 5: take the "tens" part of the number and add 1, Multiply the original "tens" part of the number by the new number. Take the result and put 25 behind it (append 25)
75 * 75 = ? ==> take the take the "tens" part of the number and add 1 ==> 7+ 1= 8 ==> multiply the original tens by the new number ==> 7 * 8 = 56 ==>Take the result and append 25 ==> 56 25
• Any number of 9: write down as many 9s less one (beginning at the left) as there are 9s in the given number, write an 8, write as many 0s as the 9s you wrote in first place, and write 1.
9999*9999 = ? ==> write down as many 9s less one ==> 999 ==> write down an 8 ==> 999 8 ==> as many 0s as the 9s you wrote in first place ==> 999 8 000 ==> write a 1 ==> 999 8 000 1

Answer 2

a million sig fig= 6 2 sig figs= 6.a million 3 sig figs= 6.thirteen significant figures are in basic terms numbers that during certainty arent 0 if u had 3.140567 to around to 4 sig figs it would be 3.1406 through fact 0 doesnt count style as one and there became right into a 6 after the 5 so u would around that to the subsequent style wish this helped :) x

Answer 3

Simple answer: Solve your math problem then round off. How much? Look at the numbers you added, multiplied, whatever. The one with the least sig figs determines how many your answer can have.

Answer 4

erm. interesting question.

0.0003 -one significant figure. you do not count the zeros in front of the number.

0.000300- 3 significant figure. you count it because it takes into consideration that accuracy of the answer- like 0.00029999 and you round it up. yup.

3.00- 3 sig. fig too.

multiplication. i don't count it. try converting into standard form. and then convert. once you get the two above. you will know. it's easy. don't stress it out

Answer 5

yes
x is times
/ is divison
and
+ is addition
- is subtraction
= this is extra credit its called equal

Answer 6

when you multiply or divide the answer is the one with the less significant figures....ex: 1.379 x 4.1 = 5.7
and when you add or substract it is the one with less decimals
ex. 1.379 + 4.10078 = 5.480