A first grade teacher uses ten flash cards, each numbered from 1 to10, to teach her students to order numbers correctly. She has students choose four flash cards randomly, then arrange the cards in ascending order. One day, she removes the cards '2' and '4' from the deck. On that day, how many different correct arrangements of four randomly selected cards are possible?	Choose the correct choice:
A) 70
B) 210
C) 336
D) 840
E) 1680
This is a combinations problem so you need to use the correct formula:   10-2= 
<gadget id="calculator">10-2</gadget>
<output>8</output>
8 total cards. all possible permutations of 4 chosen from 8 cards are 8!/4!(8!-4!)= 8!/4!*4! =8*7*6*5*/4*3*2*1* 8 /4 *4= 
<gadget id="calculator">8 /4 *4</gadget>
<output>8</output>
8*7*6*5*/4*3*2*1*=70   70NS:70
<result>A</result>
A first grade teacher uses ten flash cards, each numbered from 1 to10, to teach her students to order numbers correctly. She has students choose four flash cards randomly, then arrange the cards in ascending order. One day, she removes the cards '2' and '4' from the deck. On that day, how many different correct arrangements of four randomly selected cards are possible?