40 - 12 = 28
28 / 40 = 0.7
0.7 * 100 = 70%
The percentage decrease is 70%.
Answer:
The answer to this question is A
Answer:
- x = 10
- B. 3/7
Step-by-step explanation:
1. (x - 2)/ 4 - (3x + 5)/7 = - 3
7(x -2) -4(3x +5) = -84 . . . . . . . multiply by 28
7x -14 -12x -20 = -84 . . . . . . . . eliminate parentheses
-5x -34 = -84 . . . . . . . . . . . . . . collect terms
-5x = -50 . . . . . . . . add 34
x = 10 . . . . . . . . . . . divide by -5
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2. 1/(1 + 1/(1 - 1/x)) = 4
1 = 4(1 +1/(1 -1/x)) . . . . multiply by the denominator
-3 = 4/(1 -1/x) . . . . . . . eliminate outer parentheses, subtract 4
-3(1 -1/x) = 4 . . . . . . . multiply by the denominator
-3 +3/x = 4 . . . . . . . . eliminate parentheses
3/x = 7 . . . . . . . . . . . add 3
x = 3/7 . . . . . . . . . . . multiply by x/7
Answer: 114
Step-by-step explanation:
Plug in the numbers. 5*5+2*5*8/2*2+3*3=25+80+9=114
