Answer:
The first car was traveling 70 mph, while the second was driving 50 mph.
Step-by-step explanation:
Set the cars as a proportion:
X represents the speed of the second car. By cross multiplying, you get the following equation:
You solve by distributing 150 to get 210x = 150x + 3000.
Solving for x gets you 50.
That means the first car was going at 50 mph. Adding 20, you get 70 as the speed for the second car.
Answer:
A
Step-by-step explanation:
We know million has 6 zeros.
So, 1 million would be written as:
1,000,000
Similarly, 27 million would be written as:
27,000,000
We know writing a number in scientific notation would make this a decimal in 1 decimal place, so we would select "2.7" as the base of the scientific number.
Now, how many places to the right do we need to go (in 2.7) to make it 27,000,000?
Counting, we see: 7 places
So, power of 10 would be "7", thus we can write:
Answer choice A is right