Question

Question 7

Radha is drawing a dot Rangoli (a beautiful pattern of lines joining dots with chalk powder as shown in figure). She has 9 dots in a row. How many dots will her Rangoli have for r rows? How many dots are there if there are 8 rows? If there are 10 rows?

Answer 1

Given, number of dots in each row = 9
Number of rows = r
$\therefore$ Total number of dots in r rows = 9r

Case 1: When number of rows = 8

Number of dots in r rows = 9r

$\therefore$ Number of dots in 8 rows =$9\times 8=72$

Case 2: When number of rows = 10

Number of dots in r rows = 9r

$\therefore$ Number of dots in 10 rows = $9\times 10=90$