Answer:
I know 4 people that are all really close friends and all have birthdays in march.
Step-by-step explanation:
Answer: 639
Step-by-step explanation:
Answer:
First one is 5, second one is 6, third one is 6, the last one is 2
Step-by-step explanation:
Hope this helps an mark brainliest please!
Answer:
20/3 ounces of water is added.
Step-by-step explanation:
how many ounces of pure water should be added to 20 ounces of 40% solution of muriatic acid to obtain a 30% solution of muriatic acid?
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The acid is 40% of 20 ounces = 8 ounces.
0.4*20 = 8
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That same 8 ounces is to be 30%. The water will be the other 70%.
8/30 = x/100
30x = 800
x = 80/3, the total amount of the solution.
We started with 20, so 80/3 - 20 = 20/3
20/3 ounces of water is added.
Number of weekend minutes used: x
Number of weekday minutes used: y
This month Nick was billed for 643 minutes:
(1) x+y=643
The charge for these minutes was $35.44
Telephone company charges $0.04 per minute for weekend calls (x)
and $0.08 per minute for calls made on weekdays (y)
(2) 0.04x+0.08y=35.44
We have a system of 2 equations and 2 unkowns:
(1) x+y=643
(2) 0.04x+0.08y=35.44
Using the method of substitution
Isolating x from the first equation:
(1) x+y-y=643-y
(3) x=643-y
Replacing x by 643-y in the second equation
(2) 0.04x+0.08y=35.44
0.04(643-y)+0.08y=35.44
25.72-0.04y+0.08y=35.44
0.04y+25.72=35.44
Solving for y:
0.04y+25.72-25.72=35.44-25.72
0.04y=9.72
Dividing both sides of the equation by 0.04:
0.04y/0.04=9.72/0.04
y=243
Replacing y by 243 in the equation (3)
(3) x=643-y
x=643-243
x=400
Answers:
The number of weekends minutes used was 400
The number of weekdays minutes used was 243
