It depends on what you are trying to calculate but the most common way I go to find percentage is to multiply by the number in decimal for ie. 50% = .5.
If you are looking for a way to do it quickly in your head I always take find out what 10% is like in the case of 100 it would be 10 so if I want to find 15% I know I can find 10% and if I cut what 10% is in half I will find 5% so likewise if I add what 10%+5% I will end up with 15%. For example, 10% of 100 is 10 half of 10 is 5 and 10+5 equals 15. If you need to find something like 20% or 30% I know that I can find 10% and instead of dividing(cutting it in half) I can multiply by 2 or 3. 10% + 10% =20%
I hope it helps, if you have more questions let me know!
Answer:
-6
-21
12
Step-by-step explanation:
can i get brainly
Answer:
y = x - 4
Step-by-step explanation:
The standard equation of a line is y = mx+b
m is the slope
b is the y intercept
Get the slope
Using the coordinate points (4, 0) and (0, -4)
m = -4-0/0-4
m = -4/-4
m = 1
Since the line cuts the y axis at y = -4, the y-intercept b = -4
Get the equation;
Since y = mx+b
y = 1x + (-4)
y = x - 4
This gives the required equation
Answer:
y = .5x+30
Step-by-step explanation:

<em>hope this helps, good luck :)</em>
Answer:
Hi,
Step-by-step explanation:
The playground 's area is the difference of 2 squares:
20²-10²=(20+10)*(20-10)=30*10=300 (ft²)