Help please show work this is due soon

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

You give a $4 tip for a meal that cost $22. approximately what percent of the bill was your tip?

Merrida uses a pattern in the multiplication table below to find ratios that are equivalent to 7: 9. if merrida multiplies the first term, 7, by a factor of 6, what should she do to find the other term for the equivalent ratio? multiply 9 by 1. multiply 9 by 6. multiply 9 by 7. multiply 9 by 9.