I'm stuck on probability and factoring
(don't mind the brackets around the factorising question, i put it there)
#exam questions
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unborn crag
(a) There are 10 possibilities for each digit, so the answer is $10^4= 10000$. \ \ (b) There are $10$ possibilities for the first digit, followed by $9$ for the second, $8$ for third, and $7$ for the fourth, yielding $(10)(9)(8)(7)=5040$. \ \ (c) $\frac{10000-5040}{10000}(100)=49.6%$ \ \ (d) $\frac{28.99}{1.23} \approx 23.57$
rain sealBOT
Civil Service Pigeon
unborn crag
7 (a) $18pq-10rs-4pr+45qs$ \ $$18pq+45qs-10rs-4pr \ \ =9q(2p+5s)-2r(2p+5s) \ \ =(9q-2r)(2p+5s)$$
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Civil Service Pigeon
