Question

(i) Draw the next pattern
(ii) Prepare a table for the number of dots used for each pattern
(iii) Explain the pattern
(iv) Find the number of dots in the 25^th pattern

Answer 1

(i) The next pattern is

(ii)

Pattern Number	1	2	3	4	5
Number of dots	2	5	9	14	20

(iii)

Pattern	Number of dots
1	2
2	2 + 3
3	2 + 3 + 4
4	2 + 3 + 4 + 5

First number is 2

2^nd number is 2 + 3 = 5

3^rd number is 5 + 4 = 9

4^th number is 9 + 5 = 14

5^th number is 14 + 6 = 20

(iv) Number of dots in the 25^th pattern is

Pattern	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25
No. of dots	2	5	9	14	20	27	35	44	54	65	77	90	104	119	135	152	170	189	209	230	252	275	299	324	350

The number of dots in the 25^th pattern = 350.