How to interpolate using 991MS scientific calculator : Interpolation

How to interpolate using 

991MS scientific calculator 

Interpolation

Interpolation is an estimation of a value within two known values in a sequence of values. 

Interpolation used in findingout the value of slenderness ratio form IS 800:2007 ,in IS 456:2000 for finding the value of bond strength ,shear strength using tables.

Example 1. : If values are in increasing manner

NOW Using CASIO Fx-991MS 
As given question
15,100
25,500
Then calculate the value Q for 20 

NOW Using CASIO Fx-991MS

There are steps :

1. start-> press mode ( 2 times ) Reg-> press 2 and press 1 (Lin mode)

enter the value 15 ,100 and press M+
(Comma is compulsory )

and  next  the value 25,500 & press M+

enter the value 20 to interpolate press  shift and press num 2 > > > 2
 (y bar seen)

press = (equal to)  and get the value 300


Example 2 : If values are in Decreasing manner

As
10,500
30,200
Then calculate the value Q for 20 

Using CASIO Fx-991MS

There are steps :

1. start-> press mode ( 2 times ) Reg-> press 2 and press 1 (Lin mode)

enter the value 10 , 500 and press M+
(Comma is compulsory )

and  next  the value 30 , 200 & press M+

enter the value 20 to interpolate press  shift and press num 2 > > > 2
 (y bar seen)

press = (equal to)  and get the value 350

Calculator pictures showing steps for interpolation :
 start the calculator




-> press mode ( 2 times ) 





To select Reg -> press 2 

and select Linmode  -> press 1 (Lin mode)

enter the value 15 ,100 
(Comma is compulsory )

      and  press M+

After pressing M+ you will see the screen like this

and next the value 25,500 & press M+

enter the value 20 to interpolate 

and press  shift 

and press num 2 > > > 2 (arrow 3 times)

(y bar seen then press 2 )

press = (equal to) 

 and get the value 300

ALL the best