Final answer:
The equation representing the relationship between the principal amount, interest rate, period, and interest earned in Robert's investment is: Interest (i) = Principal (p) × Rate of interest (r) × Time (t). For Robert, who invests $1,100 at an 8% annual rate for 1 year, the calculation would be i = $1,100 × 0.08 × 1.
Step-by-step explanation:
The equation that shows the relationship between the principal amount (p), rate of interest (r), period of investment in years (t), and interest earned (i) for a simple interest investment is:
Interest (i) = Principal (p) × Rate of interest (r) × Time (t)
In the case of Robert's investment:
- Principal (p) is $1,100
- Annual interest rate (r) is 8% or 0.08 when expressed as a decimal
- Period of investment (t) is 1 year
Therefore, the equation becomes:
i = $1,100 × 0.08 × 1
This equation will calculate the interest earned by Robert after 1 year.