Answer:
let water evaporated be x ml
...
acid 8% ------60 ml
...
final quantity = 10% ----(60-x)
..
60*8 = 10(60-x)
480=600-10x
10x=600-480
10x= 120
/10
x=12 ml should be evaporated.
Step-by-step explanation:
Take a look at the picture i sent you
Those are the ranges for one tandard deviation below the mean and one standard deviation above the mean, and we know that 68% of the data falls in that range, so the probability that a randomly chosen worker makes that much is 68%
Answer:
B cuz i said so
Step-by-step explanation:
Answer:
11. x = -3+√37 ≈ 3.08276
12. x = 11.2
13. x = -6 +6√5 ≈ 7.41641
Step-by-step explanation:
In each case, the relation of interest is ...
(distance to circle near) × (distance to circle far) = (distance to circle near) × (distance to circle far)
When there is only one point of intersection of the secant with the circle—because it is a tangent—then the product is the square of the length of the tangent.
11. 2(2+12) = x(x +6)
x² +6x -28 = 0
(x +3)² -37 = 0
x = -3+√37 ≈ 3.08276
12. 5(5+x) = 9(9)
5x +25 = 81
x = 56/5 = 11.2
13. x(x +12) = 12(12)
x² +12x -144 = 0
(x +6)² -180 = 0
x = -6 +√180 ≈ 7.41641
_____
<em>Comment on this secant rule</em>
This rule turns out to apply whether the point of intersection of the secant lines is outside the circle (as in these problems) or inside the circle (as in problem 9). The product of the two distances from the point of intersection to the circle is a constant for a given pair of intersecting secants/chords.
