Question
After interchanging "×" and "÷", "7" and "4", which of
the following equations becomes correct?Solution
1. 21 ×  4 + 7  ÷ 5 = 24 ⇒ 21 ÷ 7 + 4 × 5 ⇒ 3 + 20 ⇒ 23 ≠24 2. 35 ×  4 + 7 ÷ 2 = 20 ⇒ 35 ÷ 7 + 4 × 2 ⇒ 5 + 8 ⇒ 13 ≠20 3. 7 ÷ 4 + 15 × 5 = 35 ⇒ 4 × 7 + 15 ÷ 5 ⇒ 28 + 3 ⇒ 31 ≠35 4. 140 × 4 + 20 ÷ 7 = 100 ⇒ 140  ÷ 7 + 20 × 4 ⇒ 20 + 80 ⇒ 100 = 100 Hence, option 4 is correct.
Find the wrong number in the given number series.
24, 120, 720, 5040, 40320, 362881
128, 350, 609, 898, 1222, 1583
- Find the wrong number in the given number series.
3, 15, 18, 54, 56, 51 11, 12, 20, 58, 234, 1168
48, 72, 104, 144, 192, 251Â
2, 6, 24, 96, 384, 1536, 6144
Find the wrong number in the given number series.
119, 200, 300, 417, 565
2400,3600,5400,7200,12150
8 10.4 6.8 10.2 7.6 10
7, 22, 68, 207, 620, 1880