Question

ma gandesc la un nr il inmultesc cu 5 si ii adaug 9999 rezulatatul il maresc de 6 ori il adun cu 18920 si obtin 87374 la ce nr m.am gandit? braynli  [va rog rezolvarea cu metoda inversa!]<br />​

Answer 1

[(n*5+9999)*6]+18920=87374
(n*5+9999)*6=87374-18920
(n*5+9999)*6=68454
n*5+9999=68454:6
n*5+9999=11409
n*5=11409-9999
n*5=1410
n=1410:5
n=282

Answer 2

y×5+9999=y×6+18920=87374

5y+9999= 6y+18920=87374

6y-5y+18920-9999=87374

y+8921=87374

y=87374-8921

y=78453