HELP!!!

edited June 2017
Hello,

I'm wondering if someone could please offer me some assistance when working out interpolation equations.

10% + 5510/14080 x 10 = 13.9 - 14 %

I just cant seem to get 13.9% or 14% when I work this out with a calculator. is there something I am missing out or am I just not working it out correctly?

Any help or assistance will be greatly appreciated

• edited June 2017
Looks like it works to me, maybe its the order of calculations throwing you off.

Division and multiplication first:
(5510/14080) = 0.39134
0.39134 x 10 = 3.9 (to 1 d.p)
10+3.9= 13.9% or 14% rounded up

Hope this helps.
• Thank you. But please can I ask how you are meant to know the order of those equations when in the textbook you are shown a formula to follow? Is there an easier way to reach this conclusion? I am finding this most confusing, nowhere in my AAT textbook is the equation explained the way you have explained above.

Many thanks • All mathematical calculations follow the rules of BODMAS/BIDMAS which determines the order in which to solve the equation.

Brackets
Order / Index
Division
Multiplication