What is the solution of the system

What signals you that factoring by grouping is the best method to use when factoring a problem?

Six random samples were taken each year for three years. the table shows the inferred population for each type of fish for each year.

Complete the frequency table: method of travel to school walk/bike bus car row totals under age 15 60 165 age 15 and above 65 195 column totals 152 110 98 360 what percentage of students under age 15 travel to school by car? round to the nearest whole percent.