On one day a rickshaw puller earned $80. out of his earnings he spent $68/5 on the tea and snacks, $51/2 on food and $22/5 on repairs of the rickshaw. how much did he save on that day?

Aresearch study is done to find the average age of all u. s. factory workers. the researchers asked every factory worker in ohio what their birth year is. this research is an example of a census survey convenience sample simple random sample