Let S = event that the moon is in the Seventh House, and let J = event that Jupiter aligns with Mars.

We are given that

P(SJ) = 0.05,
P(J) = 0.25, and
P(SJ) = 0.75.

We now use the formula

P(SJ)	=	P(S)	+	P(J)	-	P(SJ)
0.75	=	x	+	0.25	-	0.05,

So, x = 0.55. In other words, the moon is in the Seventh House 55% of the time.

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