I'm guessing D, but no so sure.
Answer:
x=30
Step-by-step explanation:
6 x 5 = 30
30/5 = 6
Lets call x the amount of 18% solution and y the amount of 40% solution, and write as equations the info of the problem:
18x + 40y = 10(20)
x + y = 10
lets multiply the second equation by -18 and add to the first:
18x + 40y = 200
-18x -<span> 18y = -180
</span>----------------------
0 + 22y = 20
y = 20/22 = 10/11
and substitute in the original equation:
x <span>+ y = 10
</span>x = 10 - y
x = 10 - 10/11
x = 110/11 - 10/11
x = 100/11
so they have to use 100/11 liters of 18% solution and 10/11 liters of 40% solution
Answer:
12
Step-by-step explanation:
Using the formula
A=wl
Solving for l
1=a/w=24/2=12
Answer:
30 seconds
Step-by-step explanation:
→ Work out how many floors it's going to travel
15 - 3 = 12 floors
→ Work out how many meters 12 floors is
12 × 5 = 60 meters
→ Work out how long that will take
60 ÷ 2 = 30 seconds
