As soon as possible after the lecture
Answer:

Step-by-step explanation:




Answer:
x=7
Step-by-step explanation:
25x+5=180
-5 -5
25x=175
/25 /25
Let x = first plane's speed.
We have the equation:
2 hours * x km/h + 1.5 hours * (x+60) km/h = 3135 km.
3.5 hours*x km/h + 90 km = 3135km
3.5hours*x km/h = 3045km
x = 870 km/h.
The first plane is traveling at 870 km/h, therefore since it is 60 km/h faster, the second plane is traveling at 930 km/h.
Answer:
90 of the students are girls.
Step-by-step explanation:
Boys : Girls
B : G
4 : 3
120 : ?
(120 ÷ 4 = 30) so 4 × 30 = 120
(Do this to the other side) 3 × 30 = 90
B : G
120 : 90 [90 girls out of 210 total students]
Hope this helps. :)