Answer:
x = 72 / 85
Step-by-step explanation:
x -6/7=-x/84
x + x/84 = 6/7
84/84x + 1/84x = (12*6) / (12*7)
85/84x = ( 72 ) / ( 84 )
85/84x = 72 / 84
Multiply left and right from the = sign by 84/85 and you do that so you get a division ON THE LEFT SIDE that equals as 1... See how it works:
84/85 * { 85/84 } * x = 84/85 * { ( 72 ) / ( 84 ) }
{ (84 * 85) / ( 85 * 84) } * x = ( 84 * 72 ) / ( 85 * 84 )
(7140) / ( 7140) * x =. ( 6048 ) / ( 7140)
x = 6048 / 7140
x = 72 / 85
Answer:
12 and 8
Step-by-step explanation:
set two numbers as x and y
mean of 10 → x+y/2=10
range of 4 → x-y=4
x+y=20
+ x-y=4
____________
2x=24, x=12
12-y=4, y=8
Answer:
36 passengers
Step-by-step explanation:
Maria averages 20 passengers every 20 minutes, so she places 1 passenger per minute.
Sal averages 20 passengers every 25 minutes, so he places 0.8 passenger per minute.
If they work together, they can place (1 + 0.8) passengers = 1.8 passengers per minute.
In 20 minutes, they can load
1.8 passengers/minute * 20 minutes = 36 passengers