Any DaNiu can help look on the below question(need details), many thx in advance.
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In each production lot for a certain toy, 25 % of the toys are red and 75% of the toys are blud. Half the toys are size A and half are size B. if 10 out of a lot of 100 toys are red and size A, how many of the toys are blue and size B?
A. 15 B. 25 C 30 D 35 E 40
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if r@1 = rs + r +s , then for what value of s is r@s equal to r for all values of r?
A. -1 B 0 C 1 D 1/r+1 E r
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