90.

91.

Solve the equations. (Check your answers.)

92.

93.

94.

95. A soft drink is made by mixing 4 parts of carbonated water with every 3 parts of syrup. How many milliliters of carbonated water are in 280 ml of soft drink?

96. The ratio of graduate students to undergraduates at a certain university is 8 to 5. If there are 9880 undergraduates at the university, how many graduate students are there?

Solve the formula for the given variable.

97. for .

98.

99. Crystal Lake is 6 miles wide. The total time it took Helena to Kayak back and forth across the lake was 2 hours. Her rate kayaking back was three times her rate going out across the lake. What was Helena’s rate kayaking back across the lake?

Distance

Rate

Time

Out across the lake

6 miles

Back across the lake

6 miles

TOTAL

2 hrs

Set up the equation and solve it.