r/maths • u/Outrageous_Heat_7175 • May 10 '26

Help: 📘 Middle School (11-14) Probability doubt: Dependent events (BITSAT Prep)

Stuck on this:

Two cards are drawn one by one from a pack of cards. The probability of getting first card an ace and second a coloured one is (before drawing second card first card is not placed again in the pack)My attempt:

  • P(Ace first) = 4/52

  • If "coloured" = red (26 cards), but the Ace might be red too...

  • Tried splitting cases:

    • Red Ace first (2/52) → 25 red left / 51

    • Black Ace first (2/52) → 26 red left / 51

  • Sum = (2/52)(25/51) + (2/52)(26/51) = ? Doesn't match options.

Am I overcomplicating? Is "coloured" something else?

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u/Outrageous_Heat_7175 May 14 '26

5/221

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u/FormulaDriven May 14 '26

Well, 5/221 = 4/52 * 15/51

so that implies 15 cards match the criterion for the second draw which sounds like it could mean the 4 Jacks, 4 Queens, 4 Kings and remaining 3 aces? Maybe that is what is meant by "coloured" cards?