In a jar of marbles 9 out of 15 marbles are purple. Of there are 400 marbles in the jar, how many of th are not purple? a)6
b)9
c)160
d)1000

C) 160

Step-by-step explanation:

Set up a proportion:

=

Cross multiply and solve for x:

15x = 3600

x = 240

This means in 400 marbles, 240 are purple.

To find how many are not purple, subtract 240 from 400:

400 - 240

= 160 marbles

So, 160 marbles are not purple

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional