At 6:00 A. M, Tammy noticed that the temperature in her backyard was 27 °F. At 4:00 P. M., the temperature was 12 °F higher. What change in temperature must occur for the temperature to once again be 27 °F?

A. -15°F

B. -12°F

C. +12°F

D. +15°F

Yeh answer is b this is beceuae if you have 27 and you add 12 to be able to go back to the original you must do the inverse to cancel it out

the answer is b :)

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm