Answer:
x = amount of pure acid to be added = 6.67ml
Step-by-step explanation:
George wishes to increase the percent of acid in 50ml of a 15% acid solution in water to 25% acid, how much pure acid must you add?
let
x = amount of pure acid to be added
15% of 50 + x = 25% of 50 + x
(0.15 * 50) + x = 0.25(50 + x)
7.5 + x = 12.5 + 0.25x
Collect like terms
x - 0.25x = 12.5 - 7.5
0.75x = 5
x = 5/0.75
x = 6.6666666666666
Approximately,
x = 6.67
x = amount of pure acid to be added = 6.67ml
Answer: B
Step-by-step explanation:
(f+g)(x) means f(x)+g(x). It is saying to add f(x) and g(x). Since we were given f(x) and g(x), we can directly add them together.
(f+g)(x)=4x+2+x²-6 [combine like terms]
(f+g)(x)=x²+4x-4
Now that we have found (f+g)(x)=x²+4x-4, the answer is B.
Answer: 250m
Step-by-step explanation:
Length of rectangle = 140m
Length of rectangle = diameter of semicircle = 140m
Therefore, Radius(r) = 140m / 2 = 70m
Perimeter of the shaded region:
Length of tangent at P + length of tangent at Q + shaded portion of arc(AB)
Length of tangent = diameter / 2
Length of tangent = 70m
Perimeter of a circle = 2πr = 2 × 22/7 × 70 = 440m
shaded portion = 440 / 4 = 110m
Therefore, perimeter of shaded portion equals
70m + 70m + 110m = 250m
Answer:
A. 2 1/4 + 3 2/5
B. 113/20
Step-by-step explanation: For A: All you had to do was multiply -1(-3 2/5) and that was going to make your answer positive because the negatives were going to cancel each other out.
For B: First you had to make your fractions improper fractions instead of mixed numbers. And that would make it 9/4 + 17/5. Next, since they don't have the same denominator, you would have had to find the least common multiple of 5 and 4 which is 20. So then how ever many times your denominator went in to 20, that's what you'll multiply your numerator by. 45/20 + 68/20= 113/20