# Domino can eat 12-inch pizza for 20 minutes. How long does it take for him to eat a 18-inch pizza? Note: Number 1 question in difficult for grade 7 students in the finals here at Rizal High School in Caniogan, Pasig City. The judges said that the answer isn't 30 minutes. No one got the correct answer so please...

2
by Rina03
I've heard you got 37 points... ooh... If only you were right :P You may got that gold medal ;)
Weird :P you participated the Math Quiz Bee... heard that "luck" of no. 4 but not the explanation in that question? o.O oh my... T_T
and also.. you've heard how much point I got? o.O
points*
xD

2015-12-27T20:48:37+08:00
They said the answer was 45 minutes. According to them, you must find the area of the pizza. So, it seems like the 12 in. and 18 in. is the radius. Lol, I even saw that in a mini book that have tricky problems like that. It also seems that you only needed the explanation why 30 minutes isn't the answer ☺ So, I guess I won't do the equation ;)
12 and 18 inches are diameters :-)  And yes, the answer is not 30 minutes, but exactly 45 minutes :-)
oh I thought it's radius... ._.
but if it's radius... It seems like... the answer remains the same, 45 mins.
uhm, if it's diameter, that answer will be 8.89 minutes...
nvm
• Brainly User
2015-12-28T10:01:18+08:00
Find the area of each pizza:

Pizza A = 12-inch diameter
Area = π r²
= 3.14 (6 inches)²
= 3.14 (36 inches²)
= 113.04 inches²
Consumed in: 20 minutes

Pizza B = 18-inch diameter
Area = 3.14 (9 inches)²
= 3.14 (81 inches²)
= 254.04 inches²
Consumed in: x minutes

Equation:
Let the number of minutes it takes to finish 18-inch pizza:

113.04 (x) = (20) (254.34)

x = 45

ANSWER:  It takes 45 minutes to finish an 18-inch diameter pizza.