Answer:
r = 13
Step-by-step explanation:
these angles are vertical and are congruent
8r + 6 = 9r - 7
6 = r - 7
13 = r
My answer got deleted for some reason, so here we go again. To convert a number to a percent, you multiply the number by 100. So if you had the number 2.4, you would multiply it by 100 to get 240%. After multiplying it by 100, simply add a percent sign, and you're done!
Step-by-step explanation:
-2x+3=x+12
combin like terms
-2x-x=12-3
-3x=9
x=9/-3
x=-3
Answer:
Step-by-step explanation:
Both 115 and 145 mph are above the mean. Draw a normal curve and mark these speeds. 115 mph is 1 standard deviation above the mean; 130 would be 2 standard deviations above the mean; and 145 would be 3 s. d. above it.
We need to find the area under the standard normal curve between 115 and 145. This is equivalent to the area under the standard normal curve between z = 1 and z = 3.
I used my TI-83 Plus calculator's DISTR function "normalcdf(" to calculate this area: normalcdf(1, 3) = 0.1573.
The area between z = 1 and z = 3 is 0.1573. In other words, the percentage of serves that were between 115 and 145 mph was 15.73%.
I’m thinking maybe 12 boys?