Answer:
they both has 7 slides and the presentation had a duration of 28 seconds
Step-by-step explanation:
we have to setup equation that makes them equal to each other if you know what i mean. 2x+16=3x+10
then we just solve for x
2x+16=3x+10
subtract 10 from each side
2x+6=3x
step 2 subtract 2x from each side
x=6
so both of their presentations are 7 slides long
then to find the length of their presentations we just plug in 6 to one of the equations
2(6)+16
2x6=12 12+16=28 so both of their presentations were 28 seconds
In order to determine the number of boys in the class, first, we set-up an algebraic equation. Let x = number of boys in the class. The equation is then: x + 4x = 45. This is because the number of girls is 4 times greater than the number of boys. After solving the algebraic equation, it is then determined that there are 9 boys in the Chemistry class.
Answer:
Janice and Karen could do in 1 day:
Step-by-step explanation:
To identify how much of the job could janice and caren do in 1 day, first, we must find how much of the job make just 1 person at the same rate:
If three persons make a job in 3 1/3 days, 1 person make the job in x:
- 3 persons ⇒ 3 1/3 days or 10/3 days
- 1 person ⇒ x
Then:
- (we cancel the unit "persons")
- x = 10 days
Just a person would need 10 days to complete a job, now, we're gonna divide this value in 2 to obtain the time that need two persons to complete a job:
- Time to complete a job between 2 persons =
- Time to complete a job between 2 persons = 5 days
How two persons need 5 days to complete a job (in this case, the two persons are Janice and Karen), we can make a simple rule of three to obtain the percentage made in 1 day:
- 5 days ⇒ 100% of a job
- 1 day ⇒ x
Then:
- (you can use the % if you want, the result is the same)
As you can see, <u><em>Janice and Karen just in a day could do 20% of the job</em></u>.
Answer:
2
Step-by-step explanation: