Answer:
40/9
Step-by-step explanation:
Use the work formula,
+
=
, where A is the amount of time it takes one person, B is the amount of time it takes another person, and T is the time it takes for them to work together.
Plug in the times for David and Alex alone:
+
= 
Find the least common denominator, which is 40.
+
= 
= 
Cross multiply and solve for T:
9T = 40
T = 40/9
So, if they worked together, it would take them 40/9 hours
Answer:
True speed of the car is 87 km/h.
Step-by-step explanation:
Speed = 100 km/h
hike in speed = 25 %
Let the true speed is v.

Answer:
- x > -2
- n ≤ -2 or n ≥ 8
Step-by-step explanation:
<h3>1.</h3>
Add 7x-2 to both sides and collect terms.
2x +2 -6x +7x -2 > -4 -7x +7x -2
3x > -6
x > -2 . . . . . . . divide by 3
__
<h3>2.</h3>
Solve these one at a time, and form the union of the answers.
1 +7n ≤ 15 . . . .given
7n ≤ 14 . . . . . . subtract 1
n ≤ 2 . . . . . . . divide by 7
__
-2n -2 ≤ -18 . . . given
-2n ≤ -16 . . . . . add 2
n ≥ 8 . . . . . . . . divide by -2
The solution is n ≤ -2 or n ≥ 8.
Answer:
answer =6
Step-by-step explanation:
mark me as brainliest
You have to didve the numbers