Simple magic trick!!!

You set a deck of cards from 2 to 9 excluding tens aces kings jacks and queens, then u asked your audience to pick a card in their mind. After the done that u tell them to double their value then add 5 then multiply the result with 5.After u done this you will tell them to pick another card and added to the result.You will ask them to tell you the result in order to guess their 2 cards,and you will get it for surely if their math is good...
So...how u do it lets pick 2 numbers: 3 and 5 , they double the first card value 6 then add 5=11 then multiply 11 with 5=55 then when they add the secon card to the result it will be 60.So u simply remove 25 from 60 and it will give u the result 35 so the 2 card selected 3 and 5...it will be the same with the other cards so...practice:);)
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