The first step, factoring out the constant 10, is due to the Constant Multiple Rule:
The derivative of the natural exponential function is itself! . Reversing this,
Jonathan goes to the store and purchases 3 pencils for $0.28 each , and y number of erasers for $0.38 each . Write an expression
1 answer:
The expression 1.22y is the amount spent by Jonathan.
<u>Step-by-step explanation</u>:
- The cost per pencil = $0.28
∴ The total cost of 3 pencils = 0.283 = $0.84
- The cost per eraser = $0.38
∴ The total cost of y erasers = 0.38y = $0.38y
Jonathan spent = Total cost of pencil + total cost of eraser
⇒ 0.84 + 0.38y
⇒ 1.22y
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