The sum of a rational number and a rational number is rational

In a study by Swedish researchers (Occupational and Environmental Medicine 2002; 59:517-522), 2410 women who had worked as hairdressers and given birth to children were compared to 3462 women from the general populations who had given birth.

The sales tax on the purchase of a refrigerator that costs $850 is 7 percent. What is the amount of sales tax?

Calvin had $10. When he bought 7 colored pencils and 2 notebook at $1.30 per notebook, the change was $1.10 what is the price of 1 colored pencil?

Ray Industries bought a touch screen monitor for $1200. It is expected to depreciate at a rate of 25% per year. What will the value of the monitor be in 3 years? Round to the nearest dollar.

3x^3y + 12xy - 9x^2y - 36y Rewrite the expression completely factored. Show the steps of your work.

The function f (x) = 18000 (0.52) x represents the value in dollars of a vehicle x years after it has been purchased new. What is the average rate of change in value per year between years 4 and 8? -$18000/year -$1219.87/year -$304.97/year -$0.

4x-6y=2 3x+5y=11 Jonas used the linear combination method to solve the equation shown. He multiplied the first equation by 3, and the second equation by another number to eliminate the x terms. What number did Jonas multiply the second equation by?

Larry purchase 8000 shares of a stock at a price of $7.29 a share. He sold the stock six years later at the price of $10.31 per share. What is this percent gap gain

What is the value of the expression - 7 - 5 + 4? A. -16 B. -8 C. -12 D. -6

What two numbers add up to - 3 and multiply to - 100?