Ratna , who is in Mumbai , telephones her brother Ravi in Ahmedabad and speaks for 89 seconds . She is charged Rs 1.20 for every 16 seconds or part of 16 seconds . There is also a service charge of Rs 2 / - . Study the bill carefully . How much will it cost Ratna if she speaks to Ravi for 3 minutes ? A) 14.40
B) 16.40
C) 18.40
D) 20.40

Please give explanation of your answer , please .

16.40

Step-by-step explanation:

3 min-> 180 s

180÷16≈11

11+1=12

12x1.20=14.40

14.40 + 2 = 16.40

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl