Answer:
r = 225 Mil/h speed of the airplane in still air
Step-by-step explanation:
Then:
d is traveled distance and r the speed of the airplane in still air
so the first equation is for a 4 hours trip
as d = v*t
d = 4 * ( r + 25) (1) the speed of tail wind (25 mil/h)
Second equation the trip back in 5 hours
d = 5 * ( r - 25 ) (2)
So we got a system of two equation and two unknown variables d and
r
We solve it by subtitution
from equation (1) d = 4r + 100
plugging in equation 2
4r + 100 = 5r - 125 ⇒ -r = -225 ⇒ r = 225 Mil/h
And distance is :
d = 4*r + 100 ⇒ d = 4 * ( 225) + 100
d = 900 + 100
d = 1000 miles
Pi divided by 2 is <span>1.57079632679 so anything bigger than 0 and less than that number should be between.</span>
Answer:
There are 171 members in the club
Number of boys = 38
Number of girls = 133
Step-by-step explanation:
Let
x = total members of the club
Boys = 2/9x
if there are 95 more girls than boys
Girls = 2/9x + 95
how many girls are there in club?
Total members in the club = boys + girls
x = 2/9x + 2/9x + 95
x = 2+2/9x + 95
x = 4/9x + 95
x - 4/9x = 95
9x-4x/9 = 95
5/9x = 95
Divide both sides by 5/9
x = 95 ÷ 5/9
= 95 × 9/5
= 855/5
= 171
boys = 2/9x
= 2/9 * 171
= 342 / 9
= 38
Girls = 2/9x + 95
= 38 + 95
= 133
Total = 38 + 133
= 171
There are 171 members in the club
Number of boys = 38
Number of girls = 133
11a:
3x+5=5x-57
3x-5x=-57-5
-2x=-62
x=31
11b:
2x+2x+4x+150+4x+150=360
12x+300=360
12x=360-300
12x=60
x=5
hope this helped !!
