The average height of 60 pupils in a class is 150 cm. Five of them whose height is 146 cm, leave the class and five others whose average height is 156 cm, join. The new average height of the pupils of the class (in cm) is ? Pick one:
A) 287 cm
B) 150.8 cm
C) 276 cm
D) 287 cm
E) 297 cm
Total height = 150 * 60= 
<gadget id="calculator">150 * 60</gadget>
<output>9_000</output>
9000 cm.   New average= [9000 - 5 * 146 + 5 * 156 ] / 60   = 150.8 cm.   Answer:150.8 cm
<result>B</result>
The average height of 60 pupils in a class is 150 cm. Five of them whose height is 146 cm, leave the class and five others whose average height is 156 cm, join. The new average height of the pupils of the class (in cm) is ?