Because it's decreasing, you use the formula (1-x/100)y with x the percentage decreased which is here 40, and y the number decreased which is here 90
So we get
(1-40/100) * 90
(100/100 - 40/100) * 90
60/100 * 90
5400/100
54
So 90 decreased by 40% is 54
Hope this Helps :)
Answer:
z = -10
General Formulas and Concepts:
<u>Pre-Algebra</u>
- Order of Operations: BPEMDAS
- Equality Properties
Step-by-step explanation:
<u>Step 1: Define equation</u>
-4 - (z - 6) = 12
<u>Step 2: Solve for </u><em><u>z</u></em>
- Distribute negative: -4 - z + 6 = 12
- Combine like terms: -z + 2 = 12
- Subtract 2 on both sides: -z = 10
- Divide -1 on both sides: z = -10
<u>Step 3: Check</u>
<em>Plug in z to verify it's a solution.</em>
- Substitute: -4 - (-10 - 6) = 12
- Subtract: -4 - (-16) = 12
- Simplify: -4 + 16 = 12
- Add: 12 = 12
Here we see that 12 does indeed equal 12.
∴ z = -10 is a solution of the equation.
Answer:
1050, 1200, 2550 and 5100.
Step-by-step explanation:
If the first number is x then the second is x + 1/7x.
The third = x + x + 1/7x + 300 and the fourth = x + x + 1/7x + x + x + 1/7x+ 300 + 300.
So our equation is:-
8x + 4 * 1/7x + 900 = 9900
60/7 = 9000
60x = 7*9000
x = 1050.
Therefore the 4 numbers are 1050, *1/7*1050 = 1200, 2550 and 5100.
