We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.
 
+0  
 
+1
200
1
avatar+4684 

Help #4

 Feb 23, 2018
 #1
avatar+99586 
+2

The trick here, NSS....is just to simplify the numerator first and then the denominator......so we have

 

2/5t  - 3/3t  =

 

2/5t  -  1/t          multiply the second fraction by  5 on top/bottom

 

2/5t - 5/5t   =   (2 - 5 )  / 5t   =   -3 / (5t)

 

The denominator becomes

 

1/2t  +  1/2t  =   2/2t  =  1/ (t)

 

So  we have

 

(-3/5)t  ÷ 1/t        flip the second fraction and multiply

 

-3 / (5t)  *  (t)/ 1  =    -3t / 5t   =   -3/5

 

Do you see how to do this??

 

 

Second one :

 

1/ 20   =  1/r1  - 1/75       subtract  1/75  from  both sides

 

(1/20) - (1/75)  =  1/r1

 

The common denominator  on the left is 300

 

15/300  - 4/300  =  1/r1

 

(11/300)    =  1/r1

 

To find r1, just flip both fractions over

 

300/ 11  =  r1/1

 

300/11  =  r≈  27 ohms

 

 

cool cool cool

 Feb 23, 2018

24 Online Users

avatar
avatar
avatar