Question

Help please.......




A computer can perform c calculations in s seconds. How many minutes will it take the computer to perform k calculations?

a. 60ks/c
b. ks/c
c. ks/60c
d. 60c/ks
e. k/60cs

Answer 1

60 sec in 1 min so i think its not b

Answer 2

i know the answer i want to know how to do it.

Answer 3

The speed of calculations is:

\(speed ~of~ calculations = \dfrac{calculations}{time} \)

\(speed ~of~calculations = \dfrac{c}{s} \dfrac{calculations}{second} \)

\(time = \dfrac{calculations}{speeedd~of~calculations} \)

\(\dfrac{1 ~minute}{60 ~seconds} = 1\)

\(time = \dfrac{k~calculations}{\frac{c~calculations}{s~seconds}} = \dfrac{ks}{c} seconds \times \dfrac{60~seconds}{1~minute} = \dfrac{60ks}{c} per ~minute\)

Answer 4

***A computer can perform c calculations in s seconds. How many minutes will it take the computer to perform k calculations?****

we are given a rate c calcs per s seconds
rate*time = amount
so
\[ \frac{c \ calcs}{s \ secs} \cdot t = k \ calcs\]
solve for t
\[ t = \frac{k\ s \ secs}{c} \]
that is the time in seconds. if we mutliply by 1 minute/60 secs
\[ t = \frac{k\ s}{c} \ \cancel{seconds} \cdot \frac{1 \ minute}{60 \ \cancel{seconds}}\\
t= \frac{k s}{60c} \ mins
\]

Answer 5

mathstudent messed up the conversion from seconds to minutes.

Answer 6

Is that a formula? The speed of calculations thing he mentioned?

Answer 7

rate * time = distance is a formula
you learn to figure out how far you go at a given speed.

but many problems are similar to this, and can use the same idea
when I see amount per time I think "rate"
and see if rate * time = amount makes sense. (It usually does)

Answer 8

ohh okay i see

Answer 9

i got that far

Answer 10

i don't understand from there to be honest

Answer 11

what does "x" represent in your ratio?

Answer 12

# of calculations per minute

Answer 13

good. so x is a rate: calculations per minute
so use
rate * time = amount

we know the rate. we are given an amount (k)
so we can find time , and it will be in minutes.

Answer 14

ohhhhhh okay got it

Answer 15

it takes practice to think "clearly". Lots of practice.

Answer 16

yea lots of practice ^_^ thanks phi!!

Answer 17

@phi Thanks for pointing it out.

\(time = \dfrac{k~calculations}{\frac{c~calculations}{s~seconds}} = \dfrac{ks}{c} \cancel{seconds} \times \dfrac{1~minute}{60~\cancel{seconds}} = \dfrac{ks}{60c} ~minute\)