Darko found the sum of 324 and 57 to be 894. What error did he make? Darko added 324 and 75 by mistake.
Darko did not align the digits by their place value when he set up the problem.
Darko did not regroup correctly after adding the ones digits.
Darko multiplied the numbers instead of adding them.

Martha has a deck of cards. she has lost some of the cards, and now the deck only contains nine spades, eleven diamonds, eight clubs, and twelve hearts. martha predicts that whenever she draws a card from the deck without looking, she will draw a club one-fifth of the time. which activity would best allow martha to test her prediction? a. randomly draw a card from the box and see if it is a club. b. randomly draw a card. then, continue to draw another card until all eight clubs are drawn. c. randomly draw and replace a card 120 times. then, observe how close to 30 times a club is drawn. d. randomly draw and replace a card 100 times. then, observe how close to 20 times a club is drawn.