If the coefficient of demand for the SUV is 0.75 this means that it has a relatively inelastic demand (<1). This means that there is only a little change in demand when prices change. Elastic demand (>1) on the other hand has greater changes in demand when prices change; they have lots of substitutes.
So when the price of SUV rise by 15%, and it has a coefficient of 0.75, we can expect only 11.25% decrease in its demand. Still very small. This is because SUVs do not have many substitutes for it.
Formula: (x/15%)=0.75
Then simply solve for x -> x = (0.75)(0.15) = 11.25%
