Hi,孩子们,Melody老师根据一路陪伴的SSAT考生情况,发现90%的考生,在备考英制单位换算这部分知识时,明显感到无从下手。一是因为这类题目大多不会附上转换公式(常识,美国人都知道)。二是因为美国采用是英制,中国采用是国际单位制。那么如何来应对这种情况呢?今天,Melody老师为大家增点常识,长点见识。
例题1
Model trains are built on a scale of 1 inch:1 foot. If a particular model train is 3 feet7 inches long, how many yards long would the actual train be?
A. 14.3 B. 28 C. 36 D. 43.5 E. 57.75
常识:1 foot(英尺)=12 inches(英寸)= 1/3yard(码)
解析:
3 feet 7 inches = 3*12+7 = 43 inches,
因为 scale=1inch : 1foot,
所以 the length of actual train = 43 feet = 43*1/3 yard = 14.3 yards
答案:A
例题2
What is the cost of nine ounces of cheese at $0.80 per pound?
A. $0.36 B. $0.45 C. $0.48 D. $0.52 E. $0.55
常识:1 pound (磅)= 16 ounces (盎司)
解析:
因为 1ounce=1/16 pound,
所以 9 ounces= 9*1/16 pound = 9/16 pound,
所以 cost=0.80*9/16=$0.45
答案:B
例题3
A tank of oil is three-quarters full. When full, the tank holds 56 gallons. How many quarts of oil are in the tank now?
A. 56 B. 112 C. 168 D. 192 E. 224
常识:1gallon(加仑)= 4quarts(夸脱)
解析:
The volume of oil = 56*3/4 = 42 gallon = 42*4 quarts = 168 quarts.
答案:C
例题4
Which of the following gives the number of cents in a dimes, b nickels, and c quarters?
A. a/10+b/5+c/25
B.10/a+5/b+25/c
C. 10a+5b+25c
D. a+5b+50
E. 5a+10b+50c
常识:1 dime(10分铸币)= 10 cents(美分),1 nickel(5分镍币)= 5 cents(美分),1 quarter(25分硬币)= 25 cents
解析:
a dimes, b nickels, and c quarters =(10a+5b+25c)cents
答案:C
同学们,这些常识记住了吗?一起慢慢积累吧!
名师风采
姓 名:黄新丽
职 位: 国际事业群北美项目部优秀国际学科教师
教授课程:SSAT数学;美高课程;ACT数学,科学;SAT数学;SAT2数学,物理,化学; A-Level数学,物理,化学
授课时长:6000小时