One chord of a circle is given as 20.5 cm. Then the

3960, 660, 720, 122, 180, 30

2400,3600,5400,7200,12150

210, 140, 105, 84, 70, 63, 52.5

112, 236, 374, 546, 790, 1376

88, 112, 78, 120, 64, 136

Find the wrong number in the series.

3, 6, 18, 72, 360, 2160, 15120

2824     2314      1973     1759     1634     1574

120, 136, 111, 147, 93, 162, 81

Find the wrong number in given number series.

1116, 1135, 1158, 1187, 1224, 1278.

Find the wrong number in given number series.

2658, 2654, 2681, 2645, 2999, 2918