The mean weights of three groups of students
consisting of 16, 18 and 20 students are 40.5kg, 42.50kg
and 45.00kg respectively. What is the mean weight
of all the students?
Three sets of beans l, m, and n are sold for5
for $5.00, $15.00 and $17.50 respectively
per kg. If they are mixed in the ratio of
1:3:2, what is the cost per kg of the mixture?×