If the amount of time taken to go said distance is x and the amount of time taken to go back said distance is y, then the amount of miles total is 7x+3y due to that for every hour, she adds 7 miles when going there and 3 miles for walking back. In addition, since the total amount of time is 4 hours, x+y=4 as the total time spent as well as 7x=3y due to that they're the same distance.
x+y=4
7x=3y
Dividing the second equation by 7, we get x=3y/7. Plugging that into the first equation, we get 3y/7+y=4=10y/7 (since y=7y/7). Multiplying both sides by 7 and then dividing both by 10, we get 28/10=2.8=y in hours. Since 0.1 hours is 60/10=6 minutes, and 0.8/0.1=8, 6*8=48 minutes=0.8 hours, meaning that she should plan to spend 2 hours and 48 minutes walking back
Divide the total amount of money by the total amount of feet.
477.84/32 = $14.93
hope this helps :)
Answer:
D
Step-by-step explanation:
Irrational numbers are reasonable and also real.
Surd is an example of an irrational numbers.
So as another name may be I go with option D
To solve this we are going to use the formula for the volume of a sphere:
where
is the radius of the sphere
Remember that the radius of a sphere is half its diameter; since the first radius of our sphere is 24 cm,
. Lets replace that in our formula:
Now, the second diameter of our sphere is 36, so its radius will be:
. Lets replace that value in our formula one more time:
To find the volume of the additional helium, we are going to subtract the volumes:
Volume of helium=
We can conclude that the volume of additional helium in the balloon is
approximately <span>
17,194 cm³.</span>
Answer:
d) $8,100
Step-by-step explanation:
Given information:
- Money triples every 10 years
- Initial deposit = $100
- Number of years invested = 40 years
If the money triples (multiplies by 3) every 10 years,
then in 40 years time it will triple <u>4 times</u>, as 40 ÷ 10 = 4
⇒ Account balance after 40 years = $100 × 3 × 3 × 3 × 3
= $100 × 3⁴
= $8,100
<u>Proof</u>
In 10 years time the balance of the account will be:
$100 x 3 = $300
In another 10 years time, the balance of the account will be:
$300 x 3 = $900
In another 10 years time, the balance of the account will be:
$900 x 3 = $2700
In another 10 years time, the balance of the account will be:
$2700 x 3 = $8100
