Question

Out of 50 ribbons, 30 ribbons are red and the rest are blue. How many blue ribbons are there?

• A. 30
• B. 80
• C. 20
• D. 50

Answer 1

The correct option is C 20

Total number of ribbons $=50$
Number of red ribbons $=30$
Therefore, number of blue ribbons $=50-30$

As we subtract 30 from 50 vertically, we cross out 3 rods from both numbers. The remaining number of rods is our answer.

	T	O	Tens	Ones
	5	0
-	3	0
	2	0

Here, there are 2 rods remaining, which is equal to 2 Tens. So, the number of blue ribbons is 20.
Hence, Option A is correct.