PREP1-PS-Q36

evelyn205205

In a certain deck of cards, each card has a positive integer written on it.In a multiplication game, a child draws a card and multiplies the integer on the card by the next larger integer.If each possible product is between 15 and 200, then the least and greatest integers on the cards could be



(A) 3 and 15

(B) 3 and 20

(C) 4 and 13

(D) 4 and 14

(E) 5 and 14

答案是C。看了解释：是这样说的——題意應該是抽一張牌就要乘上這張牌和其下一個號碼，所以3x(3+1)=12. 4x(4+1)=20, 13x(13+1)=182, 14x(14+1)=210。應該是4與13沒錯。

那为什么不是D呢？

dxt678

In a certain deck of cards, each card has a positive integer written on it.In a multiplication game, a child draws a card and multiplies the integer on the card by the next larger integer.If each possible product is between 15 and 200, then the least and greatest integers on the cards could be



(A) 3 and 15

(B) 3 and 20

(C) 4 and 13

(D) 4 and 14

(E) 5 and 14

答案是C。看了解释：是这样说的——題意應該是抽一張牌就要乘上這張牌和其下一個號碼，所以3x(3+1)=12. 4x(4+1)=20, 13x(13+1)=182, 14x(14+1)=210。應該是4與13沒錯。

那为什么不是D呢？

-- by 会员 evelyn205205 (2011/6/24 11:12:21)

the next larger integer 可以不在这些卡中，所以如果卡中最大数是14的话，那么the next larger integer 是15,  14*15=210

evelyn205205

In a certain deck of cards, each card has a positive integer written on it.In a multiplication game, a child draws a card and multiplies the integer on the card by the next larger integer.If each possible product is between 15 and 200, then the least and greatest integers on the cards could be



(A) 3 and 15

(B) 3 and 20

(C) 4 and 13

(D) 4 and 14

(E) 5 and 14

答案是C。看了解释：是这样说的——題意應該是抽一張牌就要乘上這張牌和其下一個號碼，所以3x(3+1)=12. 4x(4+1)=20, 13x(13+1)=182, 14x(14+1)=210。應該是4與13沒錯。

那为什么不是D呢？

-- by 会员 evelyn205205 (2011/6/24 11:12:21)

the next larger integer 可以不在这些卡中，所以如果卡中最大数是14的话，那么the next larger integer 是15,  14*15=210

-- by 会员 dxt678 (2011/6/24 11:24:01)

哦，懂了~谢谢你的点拨~