下面為大家整理的是4道SAT數學練習題的內容,后面附有詳細的答案解析。SAT數學題擁有自己的邏輯關系和解題方法,這些都是大家在備考的時候,需要格外注意的部分。下面我們一起來看看這些數學題的詳細內容吧。
1.If the graph of the function f is a line with slope 2, which of the following could be the equation of f?
3.Seven cards in a pile are numbered 1through 7. One card is drawn. The units digit of the sum of the numbers on the remaining cards is 7. What is the number on the drawn card?
Answer Choices
(A) 1
(B) 3
(C) 5
(D) 6
(E) 7
Explanation
1.The correct answer is B
The graphs of all the given functions are lines, and the equations are all in the form y=mx+b. When a linear equation is in the form y=mx+b, the slope of the graph of the equation is m, the coefficient of x. The graph of the function f is a line with slope 2, so the only choice that could be the equation of f is f(x)=2x+4.
2.The correct answer is A
If a question looks as if it requires a lot of calculating, that’s often a tip-off that something else is going on. There’s usually a quick way to find the answer. In this question, all the fractions are being multiplied and so canceling is a possibility. The denominators cancel diagonally with the numerators that follow.
The 2 from 1/2 cancels with the 2 from 2/3.
The 3 from 2/3 cancels with the 3 from 3/4.
And so on, right down to the equal sign.
After you have canceled everything that can be canceled, you are left with the fraction 1/7.
3.The correct answer is A
The sum of the numbers on all seven cards is1+2+3+4+5+6+7 , or 28. Removing a numbered card reduces the sum of the remaining cards by the number on that card. For example, if the card drawn were numbered 5, then the sum of the remaining cards would be
28-5=23, a number whose units digit is 3. Similarly, if the card drawn is numbered 1, then the sum of the numbers on the remaining cards is 27, whose units digit is 7. Therefore, the drawn card was numbered 1.
4.The correct answer is C
In order for (x,y) to satisfy (x/y)=1, it must be true that x and y are equal to each other and not equal to zero. An example of such a pair is (3,3), which is in quadrant I.
In quadrant II, all the x values are negative and all the y values are positive, so in quadrant II,x and y cannot be equal. For example, the pair (-3,3) does not satisfy the condition, since (-3/3)=-1, not 1.
In quadrant III, the x values and the y values are both negative, so it is possible for x and y to be equal. For example, the pair (-3,-3) is in quadrant III and (-3/-3)=1.
In quadrant IV,x and y cannot be equal because the x values are positive and the y values are negative. For example, the pair (3,-3) does not satisfy the condition, since (3/-3)=-1.
The quadrants that contain pairs (x,y) that satisfy the given condition are quadrants I and III only.
以上就是這4道SAT數學練習題及答案的詳細內容,包括了一些常見的知識點。大家可以在備考的時候,對此加以適當的練習和應用,測試自己在數學方面知識點的掌握情況。