math
posted by steven on .
Last year's computer model is on sale for $799. You can add more memory to the computer. Each chip of 8 megabytes of memory costs $25. How many megabytes of memory can you add if you have at most $1,000 to spend.

Money left after buying computer
= 1000799
= $201
Number of 8MB chips $201 can buy
= $201/25
= 8 chips.
Total memory upgrade
= 8*8Mb
= 64 Mb.
Note: assumes no tax payable 
AT MOST signifies that you must write and inequality to solve this problem. AT MOST signifies to write the symbol "less than or equal to". <

First write down what you know:
 You will spend $1,000 at most
 The computer's initial cost is $799
 Each chip contains 8 megabytes (MB)
 Each chips costs $25
 $1,000  $799 will give you how much money you will have left over
Now let's solve:
Let x represent the amount of megabytes you can add
$1,000  $799 (gives you the amount of money you have left over to buy extra memory) = $201
$201/$25 (gives you the number of chips you can buy) = 8
8(8) (gives you the number of megabytes you can buy  the answer!! ;D) = 64
The inequality with steps:
1,000  799
8(  ) < x
25 
201
8(  ) < x
25 
8(8) < x

64 < x
