P,Q and R together earn Rs.1800 in 9 days. P and R can earn Rs.600 in 5 days. Q and R in 7 days can earn Rs.910. How much amount does R can earn per day? Choose the correct choice from the following options:
A) s.50  B) s.70  C) s.90  D) s.100  E) s.120
Explanation :   s.50mount Earned by P,Q and R in 1 day = 1800/9= 
<gadget id="calculator">1800/9</gadget>
<output>200</output>
200 ---(1)   s.50mount Earned by P and R in 1 day= 600/5= 
<gadget id="calculator">600/5</gadget>
<output>120</output>
120	---(2)   s.50mount Earned by Q and R in 1 day= 910/7= 
<gadget id="calculator">910/7</gadget>
<output>130</output>
130	---(3)   (2)+(3)-(1)=&gt; s.50mount Earned by P , Q and 2R in 1 day   - s.50mount Earned by P,Q and R in 1 day = 120+130-200= 
<gadget id="calculator">120+130-200</gadget>
<output>50</output>
50=&gt;s.50mount Earned by R in 1 day = 50   s.50nswer : Option s.50
<result>A</result>
P,Q and R together earn Rs.1800 in 9 days. P and R can earn Rs.600 in 5 days. Q and R in 7 days can earn Rs.910. How much amount does R can earn per day?