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12 lessons,
2h 18m
Chapter 3: Recurring Decimals, Specific Multiplication, Counting Marbles and Series
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In this chapter, Binati has discussed recurring decimals and other specific cases.

Binati Sheth
An Avid Reader. A Teacher. An Aid worker. An Engineer (E&C). A Writer. Budding Art Connoisseur. A philomath. A Shōnen Otaku.

Unacademy user
maam your video is good but why are u using the hard word as meaning of word like sintillate- remarkbly witty . please use simple word
didn't hnd the last part regarding the power of 3 when it comes to flipping of coins or marbles
Binati Sheth
8 months ago
not much to understand there... It's a shortcut :) when you're given coins or marbles and they tell you like there are x marbles/coins and how many minimum tries will it take to get y outcome which could be find the bad coing/heavy marble etc.... The general formula to solve this is N number of marbles ; the number of weighings is (log N /log 3)* ,where x* is the value of x rounded up to the nearest ones. To explain, assume there are 10 marbles and one of them is heavier. find which one in the minimum amount of tries. Divide the marbles into 3 groups with 3 marbles each. Step 1.1: Start weighing with 3 marbles on each side. Scenario 1.1: The balance shows a heavier side. Go to step 1.2 with these 3 'heavy' marbles. Step 1.2 - Weigh any 2 marbles of the marbles. Scenario 1.2.1 - One of them will be greater. Sceario 1.2.2 - If they are equal, the third unused marble is the heavier. Scenario - 2.1 - The balance shows equally weighed marbles. Step 2.1 - Pick the unused set. Go to step 1.2 In any case, you dont need more than 2 operations to determine the heavier marble. For any given N, solve for x in 3^x=N' where N' is the next higher power of 3 greater than N. N'=N if N is a power of 3. .... if you try to do the explanation method with the bigger numbers, it takes a while :)
Binati Sheth
8 months ago
I don't understand anything.. Please be clear... Mam
Binati Sheth
a year ago
Okay I will try to be clear.
  1. I am Binati Sheth Let's get our calculative streak on You can find me at @binati157

  2. ABOUT ME Educator at UnAcademy Aide worker Writer Teacher Occasional Japanese Translator Amateur Landscaper, Artist.



  5. Number Systems... 2%

  6. Recurring Decimals A pure recurring fraction is a VULGAR FRACTION: 0.666...-6/9-2/3 2/3-0.6666666 Let x0.666666... 10x-6.66666... 10x 9x is Dx=(6.66666 )-(0.6666666 0.1565656 = (156-1)(1000-10) = 155/990 = 311198 ) x-6/9 i.e. 2/3

  7. MULTIPLIC ATION 8y 11 145 t 4621

  8. SPECIFIC MULTIPLICATION 111- 12.321 t 1234 321 11,121 , 2

  9. COUNTING 3 thu lont numbn +2 325 n 5 ln(n+1) 2 = Y) Ma e n

  10. ) CALCULATE NMBER OF TRIES 3 HA.numurn. Min -M-63nuo 4