 Important for :
1
468 ÷ 39 × 20 + 226 = ? + 420
» Explain it
B
468 ÷ 39 × 20 + 226 = ? + 420

? = 468 ÷ 39 × 20 + 226 – 420

= 12 × 20 + 226 – 420

= 240 + 226 – 420

? = 46

Hence, option B is correct.

2
 ( 2 288 – 31 ) + ( 8 – 6 ) 2 = (?)2

» Explain it
E
 ( 2 288 – 31 ) + ( 8 – 6 ) 2 = (?)2

 or,  (?)2 = 2 36 × 8 – 31 + 8 + 36 – 12 8

 or, (?)2 = 12 8 – 31 + 8 + 36 – 12 8

? = 13

Hence, option E is correct.

3
 2 1 + 5 1 – 4 1 = ? + 1 1 4 6 8 12
» Explain it
B
 2 1 + 5 1 – 4 1 = ? + 1 1 4 6 8 12

 ? = (2 + 5 – 4 – 1) + ( 1 + 1 – 1 – 1 ) 4 6 8 12

 = 2 + ( 6 + 4 – 3 – 2 ) = 2 + 5 = 2 5 24 24 24

Hence, option B is correct.

4
 42% of 580 + 3 of 2030 – 37% of 670 = ? 7

» Explain it
B
 42% of 580 + 3 of 2030 – 37% of 670 = ? 7

? = 243.6 + 870 – 247.9

? = 865.7

Hence, option B is correct.

5
6668 + 446.8 + 2468.28 – 8326.68 + 2248.6 = ?
» Explain it
C
6668 + 446.8 + 2468.28 – 8326.68 + 2248.6 = ?

? = 6668 + 446.8 + 2468.28 – 8326.68 + 2248.6

? = 3505

Hence, option C is correect.