Ok did your teacher say anything about not being able to use negative numbers or fractions? If not can you use fractions or negative numbers.
Do you remember when you were learning about
Least Common Multiple (LCM) ? And you were
wondering what on Earth you would ever need it for ?
THIS IS IT !
The amount of time after 8 PM when the lights will flash
together again is the LCM of 20 seconds and 30 seconds.
Do you remember how to find it ?
... When 20 is prime-factored, you have 2 · 2 · 5 .
... When 30 is prime-factored, you have 2 · 3 · 5 .
... So the Least Common Multiple of 20 and 30 is 2 · 2 · 3 · 5 = 60 .
The lighthouses will flash together again in 60 seconds after 8 PM.
That'll be 8:01 PM.
We can figure out how long Michael's trip took by realizing that 30 mph is 3 times 10 mph. Because of this, the trip home will take 1/3 the amount of time it took to go up the hill. This makes the equation 24 + 8 = 32 minutes for the whole trip.
Now we need to figure out how long the trip was. We can do this by multiplying 10 minutes by 24/60, which equals 4. This means that Michael went 4 miles there, and 4 miles back. So Michael went a total of 8 miles.
Now we know that Michael went 8 miles in 32 minutes. Now, we multiply 8 by 60/32. This gives us 15, so Michael went 15 miles per hour on average in the trip.
Answer:
A random sample of 10% of all taxplayers
Step-by-step explanation:
Smaller sample sizes may not be representive of the population
