Teresa is maintaining a camp fire. she can keep the fire burning for 4 hours with 6 logs. she wants to know how many logs (y) she needs to keep the fire burning for 18 hours. she assumes all the logs are the same how many logs does tressa need to make a 18 hour fire?

27 logs

Step-by-step explanation:

Given : Teresa is maintaining a camp fire. She can keep the fire burning for 4 hours with 6 logs.

From the given situation , it is clear that the number of log and time for fire burning are directly proportional.

The equation for direct variation :-

Put , , where y is the number of logs need to keep the fire burning for 18 hours.

Hence,she needs 27 logs to keep the fire burning for 18 hours.

126.66 m²

step-by-step explanation:

the pertinent area formula is a = πr², where r is the radius.

here, a = π(6.35 m)² = 40.32π, or approximately 126.66 m²

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