If your team consisted of only you, your sister, and your mother, then your mother would have lost 17 pounds, and your sister would have lost 18 pounds.
X+1=y+1
X-Y= 0
Hope this helped you
Because the situation represents a profit, the integer is 9.
First, let's count:
there are 26 possible outcomes for E1 (black card)
there are 4x9 = 36 possible outcomes for E2, to pick a numbered card (any color)
there are 2x9 =18 possible outcomes for E1 (black) AND E2 (numbered, spade + clower)
the probability of E1 AND E2 is the ratio of the count of possible outcomes for E1 + E2 and the count of all possible outcomes (52 choices to pick a card from the deck):
P(E1 and E2) = 18/52 (34.6%)
And as asked:
P(E1) = 26/52 = 1/2 (50%)
P(E2) = 36/52 = 9/13 (69.2%)
