SAT数学练习题实例讲解(1).

不少语法不是很牢固的童鞋看到more than、less than的SAT数学题就懵了，看不懂题意。跃跃说读题断句很重要，呵呵，为了帮助大家强化一下这种题型，跃跃收集了10多道这样的SAT数学题，下面来看一下吧，有解释的不对的地方大家给我留言 tx + 12y = -3,t is a constant,if the slope of the line is -10,what the value of t? 题目解读：tx + 12y = -3，t是常数，如果这个线性函数的斜率是-10，t是几？ 解析：原式可化为(-t/12)x – 1/4 = y，斜率为-t/12，因为斜率为-10，所以可得-t/12=-10，解得t=120 生词回顾：constant常数，slope斜率 ————————————————————————————– If 10 + x is 5 more than 10, what is the value of 2x ? 题目解读：如果10 + x是15，那么2x的值是多少 解析：2x = 10 ————————————————————————————– In the 30-day month of April,for every 3 days it rained,there were 2 days it did not rain.the number of days in April on which it rained was how much greater than the number of days on which it did not rain? A:6 在4月的30天里，每三天要下雨，然后2天不下雨，问下雨的天数比不下雨的天数多几天…很明显30除以(3+2)=6….小学学过的等式不解释 ————————————————————————————– A number is added to 9 less than twice the number. if the result is 180,what is the number? 一个数加上比它本身的2倍小9的数,结果是180，问此数是多少…..即x+(2x-9)=180，x=63 ————————————————————————————– 看一道乘法原理的试题 The three distinct points P, Q, and R lie on a line l; the four distinct points S, T, U, V lie on a different line that is parallel to line l. What is the toal number of different lines that can be drawn so that each line contains exactly two of the seven points? 简单看一下题意：三个不同的点P,Q,R位于直线l上，另外四个不同的点S,T,U,V位于另外一条直线上，两条直线平行，求只包含这七个点中两个点的直线条数。注意看contains exactly two，因此排除这两个点在直线l或与其平行的直线的可能。运用乘法原理，3*4=12 生词释义：distinct不同的，parallel平行的 ————————————————————————————– At a certain hospital,89 children were born in the month of June.If more children were born on the fifteenth of June than on any other day in June.What is the least number of children that could have been born on the fifteenth of June. 题不是很难，但要注意问的是什么，看一下题意，某医院6月份出生89个婴儿，如果15号出生的婴儿数量比其他29天都多，那么15号那天至少出生几个婴儿就可以了。 平均一天生不到3个，但必须都是整数，所以平均一下就是3个，所以15号那天生4个就够了 ————————————————————————————– If 3 more than twice a number is equal 10, what is the 4 times the number? 这个题翻译很重要啊，跃跃咋一看题目就懵了，呵呵。解释一下吧，写给看不懂题意的童鞋，先要找到if分句的谓语is，然后分别翻译谓语前后的内容就可以了，3 more than twice a number比一个数字的两倍还要大三的数，is equal 10等于10，用公式表示2x+3=10，4x=14。