Calculate a price index for 2018, 2019, and 2020 using the following information about prices. Let the market basket consist of the price of one pizza pie, two sodas, and four lattes. Let the year 2018 be the base year (with an index value of 100).

year price of pizza price of soda price of coffee

2018 $6.00 .50 cents $2.00

2019 $6.50 .52 cents $2.50

2020 $7.00 .70 cents $3.20