9514 1404 393
Answer:
see attached
Explanation:
a) One way you can try to identify the pattern is to look for the differences between the images shown, then divide those differences by 2. For example, the total number of vertical dots is 2, then 4 in patterns 2 and 4. This suggests the total number of vertical dots is equal to the pattern number..
The total number of horizontal dots is 4, then 6 in patterns 2 and 4. This suggests that the number of horizontal dots increases by 1 in each pattern. This would mean pattern 1 would have 3 total horizontal dots and 1 total vertical dot. It will look like one row of 3 dots.
Pattern 3 will have 5 total horizontal dots and 3 total vertical dots. The sequence of patterns will look like the attachment.
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b) The total number of dots in each pattern is 2×(pattern number) +1. Then the number of dots in Pattern 7 will be 2×7 +1 = 15 dots.