Answer:
1089
Step-by-step explanation:
The original number is A0CD, We have that DC0A = 9 x A0CD.
If A =1, then D = 9 and we have:
9C01 = 9 x 10C9
In order for this expression to be true, the following must also be true:
(C x 9) + 8 must be divisible by 10, which means that C x 9 must end in a 2.
The only multiple of 9 (from 9 to 81) that ends in a 2 is 72.
72 = 9 x 8.
Therefore, C must be 8 and the original number is 1089. Multiply it by 9 to check the answer:
1089 x 9 = 9,081
Therefore, 1089 is correct.
Answer:
3017.54
Step-by-step explanation:
Volume for area of circle is A = Pie ( Or in this case 3.14 ) * radius ^ 2
Plug in the numbers 3.14 * 31 ^2
31 is half the diameter or the radius
Answer = 3017.54
Answer: 
Step-by-step explanation:
Answer:
8 percent
Step-by-step explanation:
Since the formula for interest rate is the original money, the amount of years, and the inetrest rate multiplied together, we could plug it into an equation. 6000 times 4 times the ineterest rate is equal to 1920. 6000 times 4 is 24000. 1920 divided by 24000 is equal to 0.08 or 8 percent.
<h3>
Answer: y = 14</h3>
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Explanation:
The two angles involving x add up to 180 degrees. This is because they are same side interior angles (and because the horizontal lines are parallel)
So,
(angle BCF) + (angle EFC) = 180
(5x - 66) + (2x + 50) = 180
5x - 66 + 2x + 50 = 180
7x - 16 = 180
7x - 16+16 = 180+16 ... add 16 to both sides
7x = 196
7x/7 = 196/7 .... divide both sides by 7
x = 28
This will be used to help find y
Notice how the angles BCF and ACD are vertical angles, therefore they are congruent or the same measure
angle ACD = angle BCF
9y - 52 = 5x - 66
9y - 52 = 5*28 - 66 ..... replace x with 28 (since x = 28)
9y - 52 = 140 - 66
9y - 52 = 74
9y - 52+52 = 74+52 .... add 52 to both sides
9y = 126
9y/9 = 126/9 .... divide both sides by 9
y = 14
