Question

If XY × 8 = YYY, where Xand Y are digits of the numbers, then what is the value of Y?

Answer 1

Given that
XY*8 = YYY ⇒⇒⇒ Where X and Y are digits
So, X is equal to one of the digits from 1 to 9
and Y is one of the digits from 1 to 9
This can be solved as following
YYY = 100Y + 10Y + Y = Y(100+10+1) = 111Y
XY*8 = 8 (10X + Y) = 80X + 8Y
∴ 80X + 8Y = 111Y
∴ 80 X = 111Y - 8 Y
∴ 80 X = 103 Y

∴ Y = 80X/103
substitute with X = 1 to 9
X = 1 ⇒⇒⇒ Y = 0.77 ⇒⇒ unacceptable

X = 2 ⇒⇒⇒ Y = 1.55 ⇒⇒ unacceptable
X = 3 ⇒⇒⇒ Y = 2.33 ⇒⇒ unacceptable
X = 4 ⇒⇒⇒ Y = 3.11 ⇒⇒ unacceptable
X = 5 ⇒⇒⇒ Y = 3.88 ⇒⇒ unacceptable
X = 6 ⇒⇒⇒ Y = 4.66 ⇒⇒ unacceptable
X = 7 ⇒⇒⇒ Y = 5.44 ⇒⇒ unacceptable
X = 8 ⇒⇒⇒ Y = 6.21 ⇒⇒ unacceptable

X = 9 ⇒⇒⇒ Y = 6.99 ⇒⇒ unacceptable

So, The is no value of  Y to achieve ⇒⇒ XY * 8 = YYY

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I think the problem is as following:

Given that XY8 = YYY ⇒⇒⇒ Where X and Y are digits
So, X is equal to one of the digits from 1 to 9
and Y is one of the digits from 1 to 9
This can be solved as following
YYY = 100Y + 10Y + Y = Y(100+10+1) = 111Y
XY8 = 100X + 10Y + 8
∴ 100X + 10Y + 8 = 111Y
∴ 100x + 8 = 101Y
∴ Y = (100X + 8)/101
substitute with X = 1 to 9
X = 1 ⇒⇒⇒ Y = 1.07 ⇒⇒ unacceptable

X = 2 ⇒⇒⇒ Y = 2.06 ⇒⇒ unacceptable
X = 3 ⇒⇒⇒ Y = 3.05 ⇒⇒ unacceptable
X = 4 ⇒⇒⇒ Y = 4.04 ⇒⇒ unacceptable
X = 5 ⇒⇒⇒ Y = 5.03 ⇒⇒ unacceptable
X = 6 ⇒⇒⇒ Y = 6.02 ⇒⇒ unacceptable
X = 7 ⇒⇒⇒ Y = 7.01 ⇒⇒ unacceptable
X = 8 ⇒⇒⇒ Y = 8    ⇒⇒⇒ integer ⇒⇒ the correct answer

X = 9 ⇒⇒⇒ Y =8.99 ⇒⇒ unacceptable

So, The value of Y = 8