In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: the sum of all the digits of the integers from 18 to 21 inclusive is 24 ( 1 + 8 + 1 + 9 + 2 + 0 + 2 + 1 = 24 ) . what is the sum t of all the digits of the integers from 0 to 99 inclusive ? 
Options: a ) 450 , b ) 810 , c ) 900 , d ) 1000 , e ) 1100

A: c
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Q: Problem: working alone , printers x , y , and z can do a certain printing job , consisting of a large number of pages , in 12 , 16 , and 18 hours , respectively . what is the ratio of the time it takes printer x to do the job , working alone at its rate , to the time it takes printers y and z to do the job , working together at their individual rates ? 
Options: a ) 4 / 11 , b ) 1 / 2 , c ) 15 / 22 , d ) 144 / 17 , e ) 11 / 4

A: d
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Q: Problem: 1 , 6 , 24 , 60 , 120 , 210 , ___ ? 
Options: a ) 336 , b ) 366 , c ) 330 , d ) 660 , e ) 770

A:
a
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