3. Kevin weighs 57 kilograms (kg) and his father weighs 85 kg. How much less is Kevin's weight than his father's weight?

Nick has box brads. he uses 4 brads for the first project. nick let’s b represent the original number of brads and finds that for the second project, the number of brads he uses is 8 more than half the difference of b and 4. write an expression to represent the number of brads he uses for the second project.

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

Suppose that in 2008 , 840,800 citizens died of a certain disease assuming the population of teh country is 399 miliion, what is the mortality rate in units of deaths per 100,000 people?