Answer:
300 girls were there in the gym.
Step-by-step explanation:
Given:
The ratio of the number of boys to the number of girls was 4:3, after 160 boys left the gym, the ratio became 4:5.
Now, to find the number of girls in the gym.
The girls in the gym does not left, their quantity is same before and after.
So, we multiply the both ratios to make the girls ratio same:
4:3 × 5 = 20:15
4:5 × 3 = 12:15
Now, <em>we find the units of the ratio</em>.
<em>The ratio of boys dropped down by 160</em>:
20 - 12 = 8 units.
160 = 8 units
Now, dividing both sides by 8 we get:
20 = 1 unit
So, 1 unit = 20.
Now, girls = 15 units
So, 15 × 20 = 300.
Therefore, 300 girls were there in the gym.
Answer:
1. -x²-15x-1
2. -33x⁷+10x⁶-14x⁵+4x⁴+11x²-5x+32
Step-by-step explanation:
-20x^2+5x+17 - (-19x^2+20x+18)
-20x² + 19x² + 5x - 20x + 17 - 18
-x² - 15x - 1
-20x^7+10x^6-5x+15 - (13x^7+14x^5-4x^4-11x^2-17)
-20x⁷ - 13x⁷ + 10x⁶ - 14x⁵ + 4x⁴ + 11x² - 5x + 15 + 17
-33x⁷ + 10x⁶ - 14x⁵ + 4x⁴ + 11x² - 5x + 32
Answer:
-2/3
Step-by-step explanation:
This means that if a line is perpendicular to a line that has slope m, then the slope of the line is -1 / m. For example, we found that the slope of the line y = (1/2)x + 3 is 1/2. This is why any line that is perpendicular to this line would have slope -2 /1 = -2.
Z value is a numerical measurement that describe a value relationship to the mean of a group of values. The standard deviations is 1.25 above the mean is 14,500 hours.
<h3>
Given information-</h3>
The mean for the bulb is 12,000 hours.
The standard deviation for the bulb is 2000 hours.
Sample value is 14500.
To find out the how many standard deviation is 14500 mean away from the mean the z value of the mean should be calculated.
<h3>Z value</h3>
Z value is a numerical measurement that describe a value relationship to the mean of a group of values. Z value is the ratio of the difference of the sample value 
and mean 
to the standard deviation. Thus the z value for the given mean 
is,
Thus the standard deviations is 1.25 above the mean is 14,500 hours.
Learn more about the z value here;
brainly.com/question/62233
