How Many Potatoes Are We Going To Get?

Problem:
We planted loads of potatoes at the community farm. How many potatoes are there going to be per family?

What we know:

• There are 20 beds of potatoes with two rows in each bed
• Each bed is about 125 metres long
• The potatoes where dropped by the planter around  35 centimetres apart

Solution:
How much was planted?

• There are 40 rows in total, each 125 metres long
• 40 x 125m = 5000m
• since there is 1000m in a km, we planted 5km of potatoes.

• the distance between potatoes is .35 metres
• 5000m ÷ .35 = 14285
• therefore we planted about 14285 seed potatoes.

Expected crop:
We looked it up and we found the average is 10 potatoes for every seed potato you plant, that means if we plant 14285 seed potatoes then we could expect a crop of 142850 potatoes.

In a book, my dad found that for every metre of seed potatoes you plant you get a crop of 2.5 kg of potatoes.

• 5000m x 2.5kg per metre = 12500kg of potatoes

How many per household:
At the moment there are 50 households but we hope that by harvest time we will have 75 households.

• 12500kg ÷ 75 = 166kg of potatoes
• 142850 ÷ 75 = 1905 potatoes

Conclusion:
If everything works out as we hope, each houshold will get about 1900 potatoes which should weigh about 166kg.

Nana's Fish Tank: Volume Problem

PROBLEM:
If Nana wanted to change all the water in the fish tank, how many large bottles worth of water would it take?

WHAT WE KNOW:
1. One water cooler bottle is equal to 5 US gallons. Using a converter we calculated that this is 18.9 litres.
2. One litre of water weighs 1 kilogram (I found this out with a previous experiment).




SOLUTION:
1. How big is a litre?

• We measured a litre carton of milk, using a tape measure.
• It is 7.3cm x 7.3cm x 20 cm high
• 7.3 x 7.3 = 53.29 cm²
• 53.29 x 20 = 1,065.8, we rounded that off to 1,000cm³
• Conclusion: 1 litre is equal to 1000cm³

2. How big is the fish tank?

• We measured the tank and it was 44cm wide, 52 cm high and 88 cm long
• 44 x 52 x 88 = 201,344 cm³ or aprox 200,000 cm³
• Since one litre equals 1000cm³ then 200,000 ÷ 1000 = 200
• Therefore there are 200 litres in Nana's fish tank

3. How many jugs of water are needed?

• We know that one jug is 18.9 litres so 200 litres ÷ 18.9 = 10.5
• Therefore we will need aprox 10.5 jugs of water.

THINGS WE FOUND OUT:
1. 1 litre is equal to 1000 cm³ , we can use a tape measure to figure out the volume of something in litres.

2. If it is water we can also figure out how much it weighs because we know that 1 litre of water weighs 1 kg.