Answer:
Mental Math and Logic
Step-by-step explanation:
You might not have access to a calculator, so when times comes like this when you have to validate a statement if wrong or right, mental math comes in help.
You only need the approximate number to do something like mental math. Both numbers divided by each other, is really close to their whole numbers of 1 and 5, respectively. If you divide 1/5, you get 0.2, which is not what the answer is. 0.02 and 0.2 are very different answers, and you would not get 0.02 no matter how many decimals after that 1.0 and 5.0.
Which means the statement is not true based on logic and mental math.
15% of 20 gal = 0.15 * 20 gal = 3 gal, so the solution contains 3 gal of salt.
If we add <em>x</em> gal of water to the solution, we end up with (20 + <em>x</em>) gal of solution. We want the new mixture to have a concentration of 10%, or
10% of (20 + <em>x</em>) gal = 0.1 * (20 + <em>x</em>) gal = 2 + 0.1<em>x</em> gal
of salt.
The amount of salt in the tank hasn't changed. Solve for <em>x </em>:
2 + 0.1<em>x</em> = 3
0.1<em>x</em> = 1
<em>x</em> = 10 gal
Answer:
C) 0.179
Step-by-step explanation:
Since the trials are independent, this is a binomial distribution:
<u>Recall:</u>
- Binomial Distribution -->
denotes the probability of
successes in
independent trials
denotes the probability of success on each of
trials
denotes the probability of failure on the remaining
trials
denotes all possible ways to choose
things out of
things
<u>Given:</u>
<u>Calculate:</u>
Therefore, the probability that the archer will get exactly 4 bull's-eyes with 10 arrows in any order is 0.179
Answer:
0.9625
Step-by-step explanation:
Answer:
A
Step-by-step explanation:
Noting that i² = - 1
Given
(7 - 3i)(8 + 4i) ← expand factors using FOIL
= 56 + 28i - 24i - 12i²
= 56 + 4i - 12(- 1)
= 56 + 4i + 12
= 68 + 4i → A