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Mathematics · 2025 · 1 mark
CBSE 2025 · Region 6 · Set 1 · Q18
A box has 4 green, 8 blue and 3 red pens. A student picks up a pen at random, checks its colour and replaces it in the box. He repeats this process 3…
A box has $\displaystyle 4$ green, $\displaystyle 8$ blue and $\displaystyle 3$ red pens. A student picks up a pen at random, checks its colour and replaces it in the box. He repeats this process $\displaystyle 3$ times. The probability that at least one pen picked was red is :
Official answer
(C)
$\displaystyle \frac{61}{125}$
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CBSE Class 12 Mathematics past-paper question from the 2025 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.