Question

Some equations are solved on the basis of certain systems. find out the correct answer from amongst the four alternatives for the unsolved equation in the question.
$a=12\left(390\right)8,h=7\left(314\right)5,c=5(?)12$

• A. 299
• B. 289
• C. 279
• D. 280

Answer 1

The correct option is C 279

a=12(390)8⇒12+8=20a=12(390)8⇒12+8=20
20×20−10=39020×20−10=390
b=7(134)5⇒7+5=12b=7(134)5⇒7+5=12
12×12−10=13412×12−10=134
c=5(?)12⇒5+12=17c=5(?)12⇒5+12=17
17×17−10=27917×17−10=279.