To find the percent of change between the cost price and the selling price of the mobile device, we can use the formula for percent change:
\[ \text{Percent Change} = \frac{\text{New Value} - \text{Old Value}}{\text{Old Value}} \times 100 \]
In this case:
- The old value (cost price) is $558.
- The new value (selling price) is $1499.
Now we can plug these values into the formula:
\[ \text{Percent Change} = \frac{1499 - 558}{558} \times 100 \]
Calculating the difference:
\[ 1499 - 558 = 941 \]
Now, substituting this back into the formula:
\[ \text{Percent Change} = \frac{941}{558} \times 100 \]
Now perform the division:
\[ \frac{941}{558} \approx 1.6847 \]
Now, multiply by 100 to get the percent:
\[ 1.6847 \times 100 \approx 168.47 \]
Therefore, the percent of change is approximately 168.47%.