Answer:
<u>The equations system is:</u>
<u>x + y = 10</u>
<u>0.5x + 0.9y = 6</u>
Step-by-step explanation:
1. Let's review the information given to us to answer the question correctly:
Liters of 60% acid solution needed = 10
x = Number of liters of the 50% solution
y = Number of liters of the 90% solution
2. Which equation represents the total liters of acid that are needed?
There are two equations needed:
The first one related to the total liters needed, 10 in this case:
x + y = 10
The second one related to the acid concentration of the 10 liters:
0.5x + 0.9y = 10 * 0.6
0.5x + 0.9y = 6
<u>The equations system is:</u>
<u>x + y = 10</u>
<u>0.5x + 0.9y = 6</u>
Solving for x and y in the 2nd equation, we have:
0.5 (10 - y) + 0.9y = 6
5 - 0.5y + 0.9y = 6
0.4y = 6 - 5
0.4y = 1
y = 1/0.4 = 2.5 ⇒ x = 7.5 (10 - 2.5)
The scientist can mix 7.5 liters of the 50% acid solution and 2.5 liters of the 90% acid solution to get the 10 liters of the 60% acid solution.
Answer:
Step-by-step explanation:
L(d) = 189 - 7d
L(17) = 189 - 7·17 = 70 miles
After 17 days, 70 miles of track remain.
:::::
189 miles × (1 day)/(7 miles) = 27 days
It takes a total of 27 days to lay the track.
Answer- 5 11/15
First step- get the same denominator for first fraction
3 4/5 times 3/3
Second step- add the whole number
1+3=4
Third step-
12/15+14/15+4
Fourth step-
4+1 26/15
Answer - 5 11/15
Answer:
24
Step-by-step explanation:
you can find the details in the attachment.
The sum of the interior angles of all triangles is 180 degrees. This means you can set all the angles' expressions equal to 180 and solve algebraically for x.
180 = 3x + 2x + x
180 = 6x
30 = x
Answer:
30°