Kaushik786
P, Q and R are positive single integers. Does the three digit number PQR lie between 100 and 300 ?
1. Q=P+S, R=Q+0.75. S is a positive single digit integer.
2. Q=P+T+2, R=Q+3/2T. T is a positive single digit integer.
Of course, the statement I is wrong the way it is written. If R and Q are integers, R=Q+0.75 is not possible.
R would not be an integer in this case. Looking at statement II, I believe the statement I should be
1. Q=P+S, R=Q+0.75S, where S is a positive single digit integer.
Now we are concerned with only the digit in hundreds place, as tens and ones digit can take any values from 0 to 10, while hundreds digit, P, can take only 1 or 2 as values. \(R=Q+\frac{3S}{4}\)
So
S has to be a multiple of 4, that is 4 or 8.
(a) \(S=8.....R=Q+6=(P+S)+6=P+8+6\)
But R is a single digit. So S cannot be 8.
(b) \(S=4.....R=Q+3=(P+S)+3=P+4+3=P+7\)
So, R=P+7. But R is a single digit, so R can be 8 or 9. Thus P will be 1 or 2.
So PQR=1QR or 2QR
In both cases, the integer PQR will lie between 100 and 3002. Q=P+T+2, R=Q+3/2T. T is a positive single digit integer.
\(R=Q+\frac{3T}{2}\)
So
T has to be a multiple of 2, that is 2, 4, 6 or 8.
a)
T=2.....R=Q+3=(P+T+2)+3=P+2+2+3=P+7So, R=P+7. But
R is a single digit, so R can be 8 or 9. Thus P will be 1 or 2.So PQR=1QR or 2QR
In both cases, the integer PQR will lie between 100 and 300b)
T=4.....R=Q+6=(P+T+2)+6=P+4+2+6=P+12R=P+12.
But R is a single digit. So S cannot be 8.
All other values will make R even bigger than the value in case b.
Thus only case (a) possible.
D