About Soroban Expertise I have a systematic and orderly way to organize the facts in a word problem, which (usually) leads clearly to the necessary equation. I think I can help with all types of word problems.
Experience 38 years of teaching college-level math, mostly at a two-year college.
Education/Credentials BS and MS in mathematics, SUNY Albany
Sergio Monterroso wrote at 2007-10-09 01:18:00
The question tells you that Percy sold an average of 17 per day. You multiply 17 x 6= 102
Then you add what you know 19+21+6+17+11=74
Substract 74 from 102 and you have the answer 28
krazykrys wrote at 2009-10-21 21:59:51
Take the number of pets given and add them together.
19 + 21 + 6 + 17 + 11 = 74
Multiply the average of 17 pets by the 6 days.
17 x 6 = 102
Then subtract the total number of pets you know, 74, from the total of pets you should have, 102, and you will have your answer.
102 - 74 = 28
You can check it by adding your answer to the number of pets that you knew and dividing it by the 6 days.