Question

Place the cards in the right boxes in the given boxes.
(a)

(b)

Answer 1

(a) As we know that addition is commutative ie. $a+b=b+c$, therefore,

$\Rightarrow 50+20=70$ and $20+50=70$

Also, in subtraction, we subtract from the biggest positive number to get a positive answer.

$\therefore 70-50=20$ and $70-20=50$

(b) We can solve this similarly as part (a). Therefore,

$\Rightarrow 30+12=42$ and $12+30=42$

Also,

$\Rightarrow 42-30=12$ and $42-12=30$