Math Tips

[dinu_rashi]

Math Tips ​

Here are some “how-to’s” that will come in handy.
How to Round a Number
To the nearest ten
If the ones digit is 5 or more, round to the next highest ten (68 rounds to 70).
If the ones digit is less than 5, round to the next lowest ten (33 rounds to 30).

To the nearest hundred
If the tens digit is 5 or more, round to the next highest hundred (384 rounds to 400).
If the tens digit is less than 5, round to the next lowest hundred (427 rounds to 400).
To the nearest thousand
If the hundreds digit is 5 or more, round to the next highest thousand (7,602 rounds to 8,000).
If the hundreds digit is less than 5, round to the next lowest thousand (7,268 rounds to 7,000).
How to Find an Average
To find the average of several numbers, add the numbers together and then divide the sum by the number of numbers.
The average of 17, 30, 6, and 7 = 60 ÷ 4 = 15
How to Tell if Two Fractions are Equivalent
Cross multiply the fractions. If both products are the same, the fractions are equivalent.
3 and 9 3 x 24 = 72 3 and 9 are equivalent fractions.
8 24 8 x 9 = 72 8 24
5 and 3 5 x12 = 60 5 and 3 are not equivalent fractions.
8 12 8 x 3 = 24 8 12

How to Find a Percentage
To tell what percentage one number is of a second number, divide the first number by the second. Move the decimal point of the resulting quotient two places to the right.
Example: What percentage is 20 of 300?
20 ÷ 300 = .067 = 6.7%
How to Change a Fraction to a Percentage
Divide the numerator by the denominator. Move the decimal point of the resulting quotient two places to the right.
6 = 6 ÷ 15 = .4 = .40 = 40%
15
How to Change a Decimal to a Percentage
Move the decimal point two places to the right.
0.792 = 79.2%
Refer to these how-to’s until you can do them automatically.
​

 

[madurax86]

thanks
there is this new thing[not that new most of the tuition class masters teach this]to be added our maths sir at skool taught us this
but this is not actually math no one actually explained why this happens till now[or i havent heard but this works]

* Only for linear fractions
binna baga kadana lesi kramayak; sarala sadaka walata witarai

bina baga kadana isela purna kotas tiyenam(haraye mathrayata wada lawaye mathraya wadi nam)

mewage ekak ne ene
for the example i only used the maximum mathraya as 2...this works for any mathraya

a*x^2 + b*x + c```````A``````B``````C
--------------------- = ----- + ----- + ----- wage ekak ne ene
(x-d)(x-e)(x-f)```````(x-d)``(x-e)````(x-f)

oke A gana lesi krame thama (x-d)=0 karana x wala agaya(d) harayatai[ (x-d) sadaketa nathuwa ] lawayatai adesha karala sulu karana eka

A= a*d^2 + b*d + c
---------------------- ocharai
`````(d-e)(d-f)

examples;

1/(x-1)(x-2) = -1/(x-1) + 1/(x-2)
from the answer
-x+2 + x-1```````1
------------- = -----------
(x-1)(x-2)`````(x-1)(x-2)

2*x``````````6`````````4```````````2x
---------- = ---------- - ------- = -------------- [for answer] and remember only for linea fractions
(x-3)(x-2)```(x-3)``````(x-2)``````(x-3)(x-2)

* me binna baga walata english walin kiyane mokakda?
*sorry about the ` forum doesnt support more than single space at once may be because of a security reason

waradi tiyenam penanda

 

[dinu_rashi]

thanks
there is this new thing[not that new most of the tuition class masters teach this]to be added our maths sir at skool taught us this
but this is not actually math no one actually explained why this happens till now[or i havent heard but this works]

* Only for linear fractions
binna baga kadana lesi kramayak; sarala sadaka walata witarai

bina baga kadana isela purna kotas tiyenam(haraye mathrayata wada lawaye mathraya wadi nam)

mewage ekak ne ene
for the example i only used the maximum mathraya as 2...this works for any mathraya

a*x^2 + b*x + c```````A``````B``````C
--------------------- = ----- + ----- + ----- wage ekak ne ene
(x-d)(x-e)(x-f)```````(x-d)``(x-e)````(x-f)

oke A gana lesi krame thama (x-d)=0 karana x wala agaya(d) harayatai[ (x-d) sadaketa nathuwa ] lawayatai adesha karala sulu karana eka

A= a*d^2 + b*d + c
---------------------- ocharai
`````(d-e)(d-f)

examples;

1/(x-1)(x-2) = -1/(x-1) + 1/(x-2)
from the answer
-x+2 + x-1```````1
------------- = -----------
(x-1)(x-2)`````(x-1)(x-2)

2*x``````````6`````````4```````````2x
---------- = ---------- - ------- = -------------- [for answer] and remember only for linea fractions
(x-3)(x-2)```(x-3)``````(x-2)``````(x-3)(x-2)

* me binna baga walata english walin kiyane mokakda?
*sorry about the ` forum doesnt support more than single space at once may be because of a security reason

waradi tiyenam penanda

Good try and thanks alot.

 

[kalhara.rokz]

thankz a lot ......

 

[Mackenzie]

Nice thread

 

[harshafx]

ah..maru thrd eka