Question

Janine is considering buying a water filter and a reusable water bottle rather than buying bottled water. Will doing so save her money?
How much water does Janine drink in a day? She normally drinks 3 bottles a day, each 16.9 ounces.
How much does a bottle of water cost? She buys 24-packs of 16.9 ounce bottles for $3.39.
How much does a reusable water bottle cost? About $10.
How long does a reusable water bottle last? Basically forever (or until you lose it).
How much does a water filter cost? How much water will they filter?
A faucet-mounted filter costs about $28 and includes one filter cartridge. Refill filters cost about $33 for a 3-pack. The box says each filter will filter up to 100 gallons (378 liters)
A water filter pitcher costs about $22 and includes one filter cartridge. Refill filters cost about $20 for a 4-pack. The box says each filter lasts for 40 gallons or 2 months
An under-sink filter costs $130 and includes one filter cartridge. Refill filters cost about $60 each. The filter lasts for 500 gallons.
The cheapest option saves her $------- over a year.

Answer 1

Buying a reusable water bottle will save her money.
She drinks 50.7 ounces of water every day.
Each bottle of water costs around 15 cents
I would say the faucet filtered-mounted filter is the cheapest option