Answer:
The number of ways are there to paint the four buildings is 48.
Step-by-step explanation:
I) let the first building be any color. Therefore the first building can be painted with any of the 4 colors.
Therefore the first building can be colored in 4 ways.
ii) the second building can be colored in 3 ways since it cannot be colored the
same color as the first building.
iii) the third building can also be colored in 3 ways.
iv) the last building can be colored in 2 ways because it cannot be the same color as the first building or the color of the adjacent building.
Therefore the total number of ways the buildings can be colored = 4 
3 3 2 = 48.
Answer:
76.8
Step-by-step explanation:
1. We assume, that the number 31.25 is 100% - because it's the output value of the task.
2. We assume, that x is the value we are looking for.
3. If 100% equals 31.25, so we can write it down as 100%=31.25.
4. We know, that x% equals 24 of the output value, so we can write it down as x%=24.
5. Now we have two simple equations:
1) 100%=31.25
2) x%=24
where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that:
100%/x%=31.25/24
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.
7. Solution for 24 is what percent of 31.25
100%/x%=31.25/24
(100/x)*x=(31.25/24)*x - we multiply both sides of the equation by x
100=1.3020833333333*x - we divide both sides of the equation by (1.3020833333333) to get x
100/1.3020833333333=x
76.8=x
x=76.8
now we have:
24 is 76.8% of 31.25
<span><span>4a+6b=10
4a=10-6b
a=(10-6b)/4
a=(5-3b)/2
</span>
<span>2a-4b=12
2((5-3b)/2)-4b=12
(5-3b)-4b=12
5-7b=12
-7b=7
b=-1
</span>
<span>2a-4b=12
2a-4(-1)=12
2a+4=12
2a=8
a=4
a=4, b=-1 </span>
12a=48</span>
The answer is 3.1428 (very close to π actually lol)
