Question 10
Which of the following is equal to 1?
(a) 20+30+40(b) 20×30×40(c) (30−20)×40(d) (30−20)×(30+20)
Let us solve all the expressions,
For option (a),
20+30+40=1+1+1 =3.
For option (b),
20×30×40=1×1×1 =1.
For option (c)
(30−20)×40=(1−1)×1=0×1=0.
For option (d)
(30−20)×(30+20)=(1−1)×(1+1)=0×2=0.
Hence, option (b) is the answer.