Answer:
279 × 7 ≈ 2800
Step-by-step explanation:
if you have to round to the tens place, then both would be rounded up, the 7 to 10 and the 279 to 280. 10 × 280 = 2800
Answer:
14 = x and 2.5 = y
Step-by-step explanation:
For ABCD - the top is 8 and the sides are 11. 11 minus 8 is 3. 11 plus 3 equals 14, that’s x.
For GHIJ - the bottom is 8 and both sides are 5.5. So 8 minus 5.5 is 2.5. That’s y.
Answer: 54.4 mph
Step-by-step explanation:
First find the distance to the train station. If it took Carlos 4 hours to come back driving at 68 mph, the distance is:
= Speed * time
= 68 * 4
= 272 miles
This means that Carlos drove for 5 hours to cover 272 miles the first time. His average speed was therefore:
= Distance / time
= 272/5
= 54.4 mph
Answer:
<em>C. 3.8 years</em>
Step-by-step explanation:
<u>Exponential Growth
</u>
The natural growth of some magnitudes can be modeled by the equation:
Where P is the actual amount of the magnitude, Po is its initial amount, r is the growth rate and t is the time.
The actual population of deer in a forest is Po=800 individuals. It's been predicted the population will grow at a rate of 20% per year (r=0.2).
We have enough information to write the exponential model:
It's required to find the number of years required for the population of deers to double, that is, P = 2*Po = 1600. We need to solve for t:
Dividing by 800:
Taking logarithms:
Dividing by log 1.2:
Calculating:
t = 3.8 years
Answer: C. 3.8 years