At a hardware store, a tool set normally costs $80. During a sale this week, the tool set costs $12 less than usual. What percentage of the usual price is the savings? Set up the percentage number sentence based on the problem then find

,    of the usual price is the savings .

Step-by-step explanation:

Here we have , At a hardware store, a tool set normally costs $80. During a sale this week, the tool set costs $12 less than usual. We need to find What percentage of the usual price is the savings . Let's find out:

Initially we have cost as $80 , in sale it is $12 less i.e.

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So , percentage of the usual price is the savings :

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Therefore ,    of the usual price is the savings .

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.