SOLUTION: Can you please help me solve this : All 28 volunteers from ms.lullas Nicaragua service trip each rent a tool to help them complete their service projects . A shovel costs $16 per

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Question 766474: Can you please help me solve this :
All 28 volunteers from ms.lullas Nicaragua service trip each rent a tool to help them complete their service projects . A shovel costs $16 per day , and an electric sander costs $19 per day. Ms lulla gets a bill for $478, but it's not itemized . However, she needs to know how many of each tool they used for documentation purposes. How many shovels did the volunteers rent?

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let x be the number of shovels, y be the number of sanders, we know
x + y = 28
16x + 19y = 478
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solve first equation for x
x = 28 - y
substitute for x in the second equation
16 * (28 - y) + 19y = 478
448 - 16y + 19y = 478
3y = 30
y = 10 and
x + 10 = 28
x = 18
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check results with second equation
16*18 + 19^10 = 478
288 + 190 = 478
478 = 478
our answers for the number of showvels and sanders checks out :-)
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18 shovels and 10 sanders were used
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