the average height of 12 girls out of a class of 20 is 161 cm . and that of the remaining girls is 158 cm . the average height of the whole class is :
"explanation : average height of the whole class = ( 12 × 161 + 8 × 158 / 20 ) = 159.8 cms answer e"
divide(add(multiply(161, 12), multiply(158, const_10)), 20)