Krishna buy some oranges at the rate of 10 for Rs 200 and an equal number at 12 for Rs 300 he mixes both oranges together and sell them at 15 for Rs 450 find his profit percentage or loss percentagel

  33 1/3% profit

Step-by-step explanation:

Suppose Krishna buys 60 oranges at each price. At the first price, Krishna pays ...

  60·(Rs 200)/10 = Rs 1200

At the second price, Krishna pays ...

  60·(Rs 300)/12 = Rs 1500

At the selling price, Krishna receives ...

  120·(Rs 450)/15 = Rs 3600

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Krishna has paid a total of 1200 +1500 = 2700 for the oranges, and sold them for 3600. His profit percentage is ...

  (3600/2700 -1) × 100% = 33 1/3%

a4 - 3a2 - 1

step-by-step explanation:

step   1   :

equation at the end of step   1   :

  ((a4) -   3a2) -   1

step   2   :

trying to factor by splitting the middle term

2.1     factoring   a4-3a2-1  

the first term is,   a4   its coefficient is   1 .

the middle term is,   -3a2   its coefficient is   -3 .

the last term, "the constant", is   -1  

thats not a system of equations, that is a solution