The algebaraic equation required is :
2.55x + 0.7 = 16
The number of pens Hannah bought is 6
If :
x = number of pens
4 more pencils Than pens ; Number of pencils = x + 4
2 fewer erasers than pens ; number of erasers = x - 2
Total amount spent = $16
The total number of items bought is :
(x) + (x + 4) + (x - 2)
Multiplying by the cost of each :
1.25x + 0.55(x+4) + 0.75(x-2)
Hence, Total amount spent can be represented as :
1.25x + 0.55(x+4) + 0.75(x-2) = 16
1.25x + 0.55x + 2.2 + 0.75x - 1.50 = 16
2.55x + 0.7 = 16
The algebraic equation is : 2.55x + 0.7 = 16
The number of pens Hannah bought can be calculated thus :
2.55x + 0.7 = 16
2.55x = 16 - 0.7
2.55x = 15.30
x = 15.30 / 2.55
x = 6
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