Directions: What will come in place of question mark(?) in the following questions?
1
(2)-3.7 ÷ (32)–1 ×  1  = (2)?
16
» Explain it
B
(2)–3.7 ÷ (32)–1 ×  1  = (2)?
16

⇒  (2)? = (2)–3.7 ÷ (25)–1 ×  1  
24

= (2)–3.7 ÷ 2–5 × (2)–4

= (2)–3.7+5–4 = (2)–2.7

∴   ? = – 2.7

Hence, option B is correct.
 
2
(16807)–2 × (49)7 ×  1  = (7)?
343
» Explain it
A
(16807)–2 × (49)7 ×  1  = (7)?
343

(7)? = (75)–2 × (72)7 ×  1
(7)3

(7)? = (7)–10 × (7)14 × 7–3

(7)? = (7)–10+14–3

(7)? = (7)1

∴   ? = 1

Hence, option A is correct.
 
3
24.8% of 1550 – 13.2% of 1125 = ?
» Explain it
B
24.8% of 1550 – 13.2% of 1125 = ? 
 
? = 384.4 – 148.5 = 235.9

Hence, option B is correct.
 
4
68921 + 17576 = ?
» Explain it
D
68921 + 17576 = ?

? = 41 + 26 = 67

Hence, option D is correct.
 
» Explain it
D
1.96 +  23.04
 = ?

? =  1.96 + 4.8  =  6.76  = 2.6

Hence, option D is correct.