Let the number be xy ,
xy = 10x + y. when reversed = yx = 10y + x
x = 2y ........(a)
10x + y + 10y + x = 66.........(b)
10(2y) + y + 10y + 2y = 66
20y + y + 10y + 2y = 66
33y = 66
y = 66/33
y = 2
x = 2y = 2*2 = 4
Recall the original number is xy = 42.
6 + 12 = 18
18 + 24 = 42
Double the difference between every 2 numbers (12 x 2 = 24 x 2 = 8)
42 + 48 = 90
90 is the missing number
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Answer:
she earns $10 per hour, and can earn $1 in 6 minutes (60 min divided by $10)
Step-by-step explanation:
Answer:
75
Step-by-step explanation:
Let t and u represent the tens and units digits, respectively.
t = u + 2 . . . . the tens digit exceeds the units digit by 2
t + 2u = 17 . . . . the sum of the tens digit and twice the units digit is 17
Substituting for t in the second equation, we get ...
(u +2) +2u = 17
3u = 15 . . . . . . . . subtract 2
u = 5 . . . . . . . . . . divide by 3
t = u+2 = 7
The number is 75.
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<em>Check</em>
7 exceeds 5 by 2. 7 + twice 5 = 7 + 10 = 17.