Answer : Explanation : You have to actually count all the balls in the pyramid.Simple way is to count the balls in each level.So lower most level lets say 1st level has 4 x 4 balls; i.e. 16 ballsSimilarly 2nd level has 3 x 3 balls; i.e. 9 balls.3rd level has 2 x 2 balls; i.e. 4 balls.The top most level has just 1 ball.So the total number of balls is 16 9 4 1 = 30. So the image has 30 Balls in all.
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