A student scored an average of 55 marks in 3 subjects: Physics, Chemistry and Mathematics. If the average marks in Physics and Mathematics is 90 and that in Physics and Chemistry is 70, what are the marks in Physics? Choose one:  A) 86  B) 165  C) 76  D) 155  E) 26
Given M + P + C = 55 * 3= 
<gadget id="calculator">55 * 3</gadget>
<output>165</output>
165 --- (1)   M + P= 90 * 2= 
<gadget id="calculator">90 * 2</gadget>
<output>180</output>
180 --- (2)   P + C= 70 * 2= 
<gadget id="calculator">70 * 2</gadget>
<output>140</output>
140 --- (3)   Where M, P and C are marks obtained by the student in Mathematics, Physics and Chemistry.   P= (2) + (3) - (1) = 180 + 140 - 165= 
<gadget id="calculator">180 + 140 - 165</gadget>
<output>155</output>
155   Answer:155
<result>D</result>
A student scored an average of 55 marks in 3 subjects: Physics, Chemistry and Mathematics. If the average marks in Physics and Mathematics is 90 and that in Physics and Chemistry is 70, what are the marks in Physics?