My teacher taught me a simple equation for these types of problems:
(percent of solution × amount of solution) + (percent of solution × amount of solution) = (percent of solution × total amount of solution)
in simple terms: %amount + %amount = %total amount
We know don't know how much gallons of 60% solution we need so it will be represented as x. We dont know the total amount either so it would have to be both solutions added together so 50 + x. Now lets solve:
(0.60)(x) + (0.24)(50) = (0.50)(50 + x) simplify/ distribute
0.6x + 12 = 25 +0.5x get all xs on one side and numbers on other
0.1x + 12 = 25
0.1x = 13 divide both sides by 0.1 to find x
x = 130
You need 130 gallons of 60% solution.
Answer:
F) The rates are not equivalent.
Step-by-step explanation:
Consider the rates 45 mile in 8 minutes and 4 minutes to travel 25 mile. Select the statement(s) that are true. Multiple select question.
We find the unit rates
a) 45 mile in 8 minutes , we find the unit rate in miles per minute
8 minutes = 45 miles
1 minute = x
8 × x = 45 miles × 1 minute
x = 45 miles/8 minutes
x = 5.625 miles/ minute
b) 4 minutes to travel 25 miles. Find the unit rate is minutes per mile
25 miles = 4 minutes
1 mile = x
25miles × x = 4 minutes × 1
x = 4 minutes/25 miles
x = 0.16 minutes/mile
Hence, the correct option is
F) The rates are not equivalent.
Answer:
x
=
4
or
x
=
−
4
Explanation:
First divide throughout by
2
to get
x
2
=
16
Now take the square root on both sides to get
x
=
±
4
.
You may now substitute the values of
x
=
4
and
x
=
−
4
back into the original equation and check that it satisfies the equation which it does.
Step-by-step explanation:
Answer:
<h2>a) Average velocity = 278 units</h2><h2>b)
Instantaneous velocity at t = 7 seconds is 148 units</h2>
Step-by-step explanation:
a) Average velocity is the ratio of displacement to time.
We have
s(t) = t³ + t
t is in between 7 and 12
s(7) = 7³ + 7 = 350
s(12) = 12³ + 12 = 1740
Displacement = 1740 - 350 = 1390
Time = 12 - 7 = 5
Displacement = Average velocity x time
1390 = Average velocity x 5
Average velocity = 278 units
b) s(t) = t³ + t
Differentiating
v(t) = 3t² + 1
At t = 7
v(t) = 3 x 7² + 1 = 148 units
Instantaneous velocity at t = 7 seconds is 148 units
Answer: 9x2 + 15x -6
Step-by-step explanation: ( 3x + 6) (3x -1)
9x2 - 3x + 18x - 6
= 9x2 + 15x -6
