Jacob's water tank can hold up to 50 liters of water. Jacob collects water from the river and rain to fill his water tank. He can collect 800 milliliters of water from the rain and 1700 milliliters of water from the river every day. How many days does Jacob need to fill up his water tank?
Jacob collects 800+1700= <<800+1700=2500>>2500 milliliters of water from the river and rain every day.
Since 1 liter is equal to 1000 milliliters, then 50 liters is equal to 50x1000= <<50*1000=50000>>50,000 milliliters of water.
Therefore Jacob needs 50,000/2500= <<50000/2500=20>>20 days to fill his water tank.
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