Ratio And Proportion
A ratio compares two quantities. When your dadi makes chai for two, she uses 1 cup water and 1 cup milk, that is a 1 to 1 ratio. When she makes pulao, she uses 1 cup rice for 2 cups water, a 1 to 2 ratio. The ratio is t…
There is more than one way to understand this. If you have only been taught one, you have been taught less than you deserve.
There is more than one way to understand this. If you have only been taught one, you have been taught less than you deserve.
A ratio compares two quantities. When your dadi makes chai for two, she uses 1 cup water and 1 cup milk, that is a 1 to 1 ratio. When she makes pulao, she uses 1 cup rice for 2 cups water, a 1 to 2 ratio. The ratio is the recipe in compressed form.
Proportion is the trick of scaling a ratio up or down without breaking it. If 1 cup rice needs 2 cups water, then 3 cups rice need 6 cups water. The ratio 1 to 2 is the same as the ratio 3 to 6. Multiply both sides by the same number, and the recipe still works.
Maps use ratios too. A road map of Pakistan might use a scale of 1 cm equals 50 km. The road from Lahore to Karachi is around 1200 km long. Divide 1200 by 50 to get 24. So that road is 24 cm long on the map. The map ratio lets a small piece of paper hold a huge country.
Currency exchange is a ratio. If 1 US dollar costs about 280 Pakistani rupees today, then 100 dollars cost 28000 rupees, and 1000 dollars cost 280000 rupees. The exchange rate is just a ratio of one currency to another. The number changes daily but the math stays the same.
Today's habit. Pick one recipe at home that you know well. Write its ratios. Now scale it for half the people, and for double the people. Read your scaled recipe to your mother and ask if it matches what she would actually do. Adjust if she corrects you.
Estimated time: 15 min