# Khan/khan-exercises

fix per eater

1 parent 5eb094f commit 3a2a3201e3aa16143fc3b11b38d2cd5fd3047c26 yunfangjuan committed Oct 16, 2012
Showing with 18 additions and 10 deletions.
1. +18 −10 exercises/exponential_growth_word_problems.html
 @@ -34,20 +34,23 @@

END_AMOUNT

- The interest rate is RATE% so the contribution - will multiply by MULTIPLIER - a year. + The interest rate is RATE%. So after each year + we have 100% of the money we started with, + plus another RATE% in interest. In other words, + we will have MULTIPLIER + times off the money we started with at the end of the year.

-

With the beginning amount of $BEGIN_AMOUNT, + With the beginning amount of +$BEGIN_AMOUNT, after one year, the contribution will grow to $BEGIN_AMOUNT \times MULTIPLIER . - After 2 years, the contribution will grow to + After 2 years, the contribution will grow to$BEGIN_AMOUNT \times MULTIPLIER \times MULTIPLIER = $BEGIN_AMOUNT \times MULTIPLIER^2 @@ -72,8 +75,8 @@ After PERIODS years,$END_AMOUNT is available to pay for person(1)'s college from - he(2) === "he"? "Uncle":"Auntie" person(2) - 's initial contribution of $BEGIN_AMOUNT. + he(2) === "he"? "Uncle":"Auntie" person(2)'s + initial contribution of$BEGIN_AMOUNT.

@@ -115,9 +118,14 @@

-

The return rate for the bank CD is RATE_BANK% so - the investment will multiply by MULTIPLIER_BANK - a year.

+

+ The return rate for the bank CD is RATE_BANK%. + So after each year we have 100% of the money + we started with, plus another RATE_BANK% in interest. + In other words, if we invest the money in the bank CD, we will have + MULTIPLIER_BANK + times off the money we started with at the end of the year. +

With the beginning amount of \$BEGIN_AMOUNT, after PERIODS years, the investment will grow to