contestada

Alan has forgotten his 4-digit PIN code.
He knows the first digit is 9 and the last digit is larger than 5.
How many different sets of 4 digits could it be?

Respuesta :

mhanifa

Answer:

  • 400 sets

Step-by-step explanation:

  • First digit- 1 option (9)
  • Second digit - 10 options (0 to 9)
  • Third digit - 10 options (9 to 9)
  • Fourth digit - 4 options (6, 7, 8, 9)

Possible number of sets:

  • 1*10*10*4 = 400