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:
D, A, I cannot read the rest of #3, C, C.
Step-by-step explanation:
We went from -12 degrees to 27 degrees.
27 - (-12) = 27 + 12 = 39
The interest due on the first payment is
.. I = Prt
.. I = 110,000*.055*(1/12)
.. I = 504.17
Then the decrease in principal resulting from the first payment is
.. 568.00 -504.17 = 63.83
and the new balance is
.. $110,000.00 -63.83 = $109,936.17
Answer:
1. 5/3 cm
2. 10 in
Step-by-step explanation:
1. The length of a rectangle is 4 cm more than 3 times its width.
Let the length be L and the width B
Then,
L = 4 + 3B
If the area of the rectangle is 15 cm2
Area = LB = 15
B(4 +3B) = 15
3B² + 4B - 15 = 0
3B² - 5B + 9B - 15 = 0
B(3B - 5) + 3(3B - 5) = 0
(3B - 5)(B + 3) = 0
3B - 5 = or B + 3 = 0
B = 5/3 or -3
since B cannot be negative, B = 5/3 cm
2. The ratio of length to width in a rectangle is 2 ∶ 3.
Let the length be L and the width B
Then,
L/B = 2/3
2B = 3L, B = (3/2)L
when the area is 150 in2.
Area = LB = 150
(3/2)L² = 150
L² = 150×2÷3
L² = 100
L = √100
L = ±10
since the length cannot be negative, L = 10 in