76. 6441-!-item-!-187;#058&005031 Is the integer k divisible by 4 ?
(1) 8k is divisible by 16.
(2) 9k is divisible by 12.
-------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】B 【思路】 (1) (2)
8k為整數,表示k可被2整除。但不表示一定可被4整除。←選項(1)不成立 169k為整數,表示3k可被4整除 =>即k可被4整除。←選項(2)成立 12--------------------------------------------------------------------------------------------------------------------------------------------------------
77. 6741-!-item-!-187;#058&005163
If n is an integer between 10 and 99, is n < 80 ?
(1) The sum of the two digits of n is a prime number.
(2) Each of the two digits of n is a prime number.
-------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】B
【思路】10 (1)兩個數相加為值數,有可能為: 94(相加為13) 已大於80。←選項(1)不成立 (2)兩位數皆為質數,表示選擇在一位數的質數 {2,3,5,7} 所得出最大的兩位數為75,小於80。←選項(2)成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 78. 6841-!-item-!-187;#058&005248 For each customer, a bakery charges p dollars for the first loaf of bread bought by the customer and charges q dollars for each additional loaf bought by the customer. What is the value of p ? (1) A customer who buys 2 loaves is charged 10 percent less per loaf than a customer who buys a single loaf. (2) A customer who buys 6 loaves of bread is charged 10 dollars. -------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】C 【思路】由題目可得知價格公式為: p+q?(n-1) *n為總購買數量 (1)由此可另外得知 (2) 由此可另外得知 p+5q=6,但無其他資訊可求出p、q。←選項(2)不成立 (1) + (2) 可聯立解兩方程式,因此可求出p ←選項(1))+(2)成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 79. 6946-!-item-!-187;#058&005390 If the terms of a sequence are t1, t2, t3, . . . , tn, what is the value of n ? (1) The sum of the n terms is 3,124. (2) The average (arithmetic mean) of the n terms is 4. -------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】C 【思路】 (1)由此可得知 t1+…+ tn = 3124,但無其他資訊求得n ←選項(1)不成立 (2)由此可得知 p?q2 = (1-0.1)p,但無其他資訊可求出p、q ←選項(1)不成立 t1?...?tnn=4,但無其他資訊求得n。←選項(2)不成立 (1) + (2) 可聯立解兩方程式,因此可求出p ←選項(1))+(2)成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 80. 7243-!-item-!-187;#058&005480 If x is a negative number, what is the value of x ? (1) x2 = 1 (2) x2 + 3x + 2 = 0 -------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】A 【思路】已知x為負數 (1) x2 = 1,且x為負數 => x= -1 ←選項(1)成立 (2) x2 + 3x + 2 = 0 => (x+2)(x+1)=0 => x=-2 或 -1 ←選項(2)不成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 81. 7301-!-item-!-187;#058&005482 D A C B In the figure above, what is the ratio KNMN (1) The perimeter of rectangle KLMN is 30 meters. (2) The three small rectangles have the same dimensions. -------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】B 【思路】*設其他點以利說明 (1) 已知長方形KLMN的周長為30,但無法得知其他資訊←選項(1)不成立 (2) 已知三個小的面積一樣,且有共用邊(ex:AD為LDAC和MDAB的共用邊)可推出AC=AB。三個長方形的面積相等,表示LDAC=CKNB (設共用邊BC為2k)=> 長*k=2K*寬 =>可得知長為2k,寬為k。KN=2k,MN=3k即可求出 KNMN. ←選項(2)成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 82. 7356-!-item-!-187;#058&005489 Is (1) x2 > y2 (2) x > y -------------------------------------------------------------------------------------------------------------------------------------------------------- x>y? 【答案】A 【思路】 (1) x2 > y2 平方已將正負數的影響拿掉(等同於絕對值) ←選項(1)成立 (2) x > y 的情況下,y有可能為負數。如此一來y的絕對值不一定小於x。 ←選項(2)不成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 83. 7463-!-item-!-187;#058&005565 If u, v, and w are integers, is u > 0 ? (1) u = v2 + 1 (2) u = w4 + 1 -------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】D 【思路】已知u,v,w皆為整數 (1) 在此情況下,v的平方一定大於0且1也大於0,所以兩的大於0的數相加一定大於0 ←選項(1)成立 (2) 在此情況下,w的四次方一定大於0且1也大於0,所以兩的大於0的數相加一定大於0 ←選項(2)成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 84. 7517-!-item-!-187;#058&005572 If p is a prime number greater than 2, what is the value of p ? (1) There are a total of 100 prime numbers between 1 and p + 1. (2) There are a total of p prime numbers between 1 and 3,912. -------------------------------------------------------------------------------------------------------------------------------------------------------- 【答案】D 【思路】 (1) 從1開始署到第101(2不是)的質數即是p ←選項(1)成立 (2) 數1~3912有幾個質數,即可得知p ←選項(2)成立 -------------------------------------------------------------------------------------------------------------------------------------------------------- 85. 7713-!-item-!-187;#058&005641 Is k positive? (1) k is between -2 and 3 on the number line. (2) k is between 1 and 2 on the number line.