Understand what is a modulo b = r and simple problems based on it. Understand the meaning of a congruent to b modulo n and problems based on these. Also mentioned are properties on these.

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Learn how to find the remainder when 2 large numbers are added or multiplied. Also, understand how we calculate the last digit or last 3 digits of a product. How do you find the last digit in 17 to the power 17?

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What is an arithmetic function? What is an additive and multiplicative function? What about completely additive and completely multiplicative functions? This lesson teaches you all this and gives examples of a number of basic arithmetic functions and how to use them. You will also learn how to calculate the time 400 hours from now or the current time if the time at a much later date is given. The concept of 12 hour and 24 hour clock are also discussed. This video is available at a small fee. You can contact me for details.


In what ratio must 2 types of fruits worth Rs 30 per kg and Rs 45 per kg be mixed respectively to get a mixture of Rs 40 per kg?

The cost of an item A is Rs 60 per kg and that of B is Rs 80 per kg. If both types are mixed in the ratio 2 :3 respectively, find the price per kg of the mixed items.

A vessel contains a mixture of 2 liquids X and Y in the ratio 3:5, 8 litres of mixture are drawn and 8 l of liquid X is filled. If the ratio of liquids X,Y is 7:10 respectively, how many litres of X and Y are contained initially?

And more problems!

Problems are explained with the relevant formula.This video explains alligation problems which is a part of Applied Math CBSE .Contact me in case you would need to purchase it.