Find (4.54 x 10^8) - (3.98 x 10^8). When you regroup the decimals,
what do you notice about their difference? How does this affect the
exponent of the difference?

$250 deductible means jane must pay the first $250 of her bill. so the insurance company paid = (80% of bill) - deductible = (0.8 x $2550) - $250 = $2040 - $250 = $1790 and jane's cost is = (bill) - (insurance payment) = $2550 - $1790 = $760

X=-4 the correct answer