下面是北外ACt给考生整理的数学练习题,考生参考下面的详细内容,希望可以帮助到ACT考生,北外ACT预祝考生考试顺利。
A rectangular lot that measures 150 ft by 200 ft is completely fenced. What is the approximate length, in feet, of the fence?
F. 300
G. 350
H. 400
J. 700
K. 1,400
解析:The correct answer is J. To find the length of fence needed to fence a rectangular lot 150 ft by 200 ft, you need to find the perimeter. The formula for the perimeter of a rectangle is 2 times the sum of the length and width, or P = 2( l+ w). 2(150 +200) =2(350) =700.
正确答案选J。所需篱笆的长度即为这块长150英尺宽200英尺矩形土地的周长。根据矩形周长公式,可知:矩形周长=2(长+宽),即2(150 +200) =2(350) =700英尺。
The expression a[b+(c-d)] is equivalent to:
A. ab + ac - ad
B. ab + ac + ad
C. ab + ac - d
D. ab + c + d
E. ab + c - d
解析:The correct answer is A. To find an equivalent expression, multiply a by b+c-d. This results in a(b) + a(c) + a(-d), or ab + ac - ad.
正确答案选A。根据乘法分配率展开括号可得ab + ac - ad。