MHB 07 division by doubling method

[karush]

use doubling method
$\dfrac{972}{69}$
$1 \to \boxed{69}+\boxed{a}=\boxed{?}$
$2 \to \boxed{138}+\boxed{b}=\boxed{?}$

is a 100 then what is b?

 

[Kansas Boy]

Where did you get "a= 100"? The title says "doubling". I would say 69+ 69= 138, then 138+ 138= 276.