Answer:
The answer would be C. 200 mph.
Step-by-step explanation:
200 times 4 is 800
The answer is actually choice A
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If we add up the equations straight down we will have 0a+2b = 6
Note how adding the 'a' terms gives us 3a + (-3a) = 3a-3a = 0a. The 0a term is really 0 since 0 times anything is 0. So the 'a' terms will go away
The equation 0a+2b = 6 turns into 0+2b = 6 and that simplifies to 2b = 6
To isolate b, we divide both sides by 2
2b = 6
2b/2 = 6/2
b = 3
We can stop here since only one answer choice has b = 3, which is choice A. However, let's keep going to find the value of 'a'
Plug b = 3 into any equation with 'a' and 'b', then solve for 'a'
3a+4b = 9
3a+4*3 = 9
3a+12 = 9
3a+12-12 = 9-12
3a = -3
3a/3 = -3/3
a = -1
So a = -1 and b = 3 pair up to form (a,b) = (-1,3)
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To check, plug this ordered pair back into both equations
Equation 1:
3a+4b = 9
3*(-1)+4*3 = 9
-3+12 = 9
9 = 9
Equation 1 has been checked out
Equation 2:
-3a-2b = -3
-3(-1)-2(3) = -3
3 - 6 = -3
-3 = -3
this is true as well
So this confirms that the final answer is choice A
Answer:
60 oz of water to add
45 oz of 35% salt solution should be used
Step-by-step explanation:
Let x = amt no. ounces in the first solution
and 105 - x = amt no. of ounces in the second solution
Ist solution contains 0% salt
2nd solution contains .35(105 - x) salt
.15(105= amt of salt in mix
So.
amt of salt in 1st solution + amt of salt in 2nd solution = amt of salt in the mix
0 + .35(105 - x) = .15(105)
Let's get rid of the fractions by multipying thru the equation by 100
35(105 - x) = 15(105)
3675 - 35x = 1575
-35x = -2100
x = 60 oz of water to add
105 - 60 = 45 oz of 35% salt solution should be used
C =
r
9.5 = 2
r
r = 4.75
r = 1.511971959
The number above should be rounded to the nearest 2 decimal places, so the answer is 1.51.
Answer:
P(A) = 1/2
Step-by-step explanation:
The question seems incomplete, I assume that we want to find the probability of event A.
Here we have a fair six-sided dice, so each one of the six numbers has exactly the same probability of being rolled.
Such that the possible outcomes of rolling the dice is:
{1, 2, 3, 4, 5, 6}
Now we define event A as rolling an even number.
The possible outcomes such that the event A is true are the even numbers:
{2, 4, 6}
So we have 3 outcomes out of 6.
Then the probability of rolling an even numbers, is just the quotient between the number of outcomes of even numbers (3) and the total number of outcomes (6).
Then:
P(A) = 3/6 = 1/2 = 0.5
