Answer:
Step-by-step explanation:
Amount of water in tank 1 = amount of water in tank 2
30t +25 = -20t + 1000
Add 20t to both sides
30t + 20t + 25 = -20t + 20t + 1000
50t + 25 = 1000
Subtract 25 from both sides
50t + 25 - 25 = 1000 - 25
50t = 975
Divide both sides by 50
t = 975/50 = 39/2

t = 19 minutes 30 seconds
After 19 1/2 minutes both tanks will have 610 liters of water
(x+7)(x+3) so therefore you set each equation = 0...
x + 7 = 0
x + 3= 0
and solve
x = -3
x = -7
Answer:
r = 4
General Formulas and Concepts:
<u>Pre-Alg</u>
- Order of Operations: BPEMDAS
- Equality Properties
Step-by-step explanation:
<u>Step 1: Define equation</u>
-5 + 22 = r - 4 + 3r + 5
<u>Step 2: Solve for </u><em><u>r</u></em>
- Combine like terms: 17 = 4r + 1
- Subtract 1 on both sides: 16 = 4r
- Divide 4 on both sides: 4 = r
- Rewrite: r = 4
<u>Step 3: Check</u>
<em>Plug in r to verify it's a solution.</em>
- Substitute: -5 + 22 = 4 - 4 + 3(4) + 5
- Add/Subtract: 17 = 3(4) + 5
- Multiply: 17 = 12 + 5
- Add: 17 = 17
Answer:
b. the area to the right of 2
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X, which is also the area to the left of Z. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X, which is the area to the right of Z.
In this problem:




Percentage who did better:
P(Z > 2), which is the area to the right of 2.
Step-by-step explanation:
cos 45° = distance to east / total distance=7,2
distance to east = cos 45° * 7,2 = 5,1 km