make a equation then solve any help is soooooo great
Ron can make as many pizzas in 30 minutes as jess can make in 40 minutes. how long will it take to make the same number if they both worked?
2006-11-13 00:59:46 · 12 answers · asked by lisaloo22610 1 in Science & Mathematics ➔ Mathematics
let the amount of pizzas equal x
ron makes x/30 pizzas per minute and jess makes x/40 pizzas per minute
together they make: x/40+x/30 pizzas per minute
=7x/120 pizzas per minute
therefore to make x pizzas they will take 17.14 (=120/7) minutes
They make 7 times the amount needed in 120 minutes therefore we must divide the 120 by 7.
2006-11-13 01:17:34 · answer #1 · answered by Anonymous · 0⤊ 0⤋
ron : x pizzas in 30 minutes
jess : x pizzas in 40 minutes
ron : 1 minute = 30/x pizzas (120/4x)
jess : 1 minute = 40/x pizzas (120/3x)
ron + jess : 1 minute = 120/7x pizzas
ron + jess : 1 minute = 120/7x pizzas
ron + jess : 120/7x pizzas = 1 minute
ron + jess : x pizzas = ? minutes
ron + jess : x pizzas = 17.142857 minutes
2006-11-13 09:18:58 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Let x = the time for them to do the job together
Then Ron does x/30 of the job and Jess does x/40 of the job.
Thus x/30+x/40 =1 {1 means job is done}
(30x + 40x )/1200 = 1
70x =1200
x= 17.143 minutes
2006-11-13 09:53:00 · answer #3 · answered by ironduke8159 7 · 0⤊ 0⤋
Ron's rate is x/30 and Jess's is x/40.
Their combined rate is x/30 + x/40= 7x/120.
The time it takes to make x pizzas when they work together
is x/(7x/120) = 120/7 =17 minutes and 8.6 seconds
2006-11-13 09:15:43 · answer #4 · answered by albert 5 · 2⤊ 1⤋
x is the number of pizzas, R is the speed of Ron, J is Jess's speed. Assume that the combination is no greater than the sum of its parts...
R= x / 30
J= x / 40
4x / 120 + 3x / 120 = 7x(pizzas) / 120(mins)
120 mins / 7x pizzas * 1x pizza = 120/7 = 17.142857...
or
17 mins 8.57 seconds
2006-11-13 10:36:57 · answer #5 · answered by C D 3 · 0⤊ 0⤋
To make 1 pizza ron takes 1/30min
To make 1 pizza jess takes 1/40min
They together will make 1 pizza in1/30+1/40min
=7/120min
so total time to make required pizza=120/7min
2006-11-13 09:12:35 · answer #6 · answered by Dupinder jeet kaur k 2 · 0⤊ 2⤋
r=ron
j=jess
r=1/30
j=1/40
r+j=1/30+1/40=4/120+3/120=7/120
total time is 120/7 min=17 min 9 sec
2006-11-13 11:23:07 · answer #7 · answered by yupchagee 7 · 0⤊ 0⤋
Ron makes 2x pizzas/hour (x pizzas in 1/2 hour).
Jess makes 1.5x pizzas/hour (x pizzas in 40 minutes).
Together, they could make 3.5x pizzas/hour.
So, it would take them 60/3.5 minutes.
2006-11-13 09:18:30 · answer #8 · answered by Engineer-Poet 7 · 0⤊ 0⤋
17 min
2006-11-13 15:41:57 · answer #9 · answered by Anonymous · 0⤊ 0⤋
around 17 min
2006-11-13 09:44:14 · answer #10 · answered by Olha K 2 · 0⤊ 0⤋