The course length of the boston marathon is about 4.2×104 meters. the course length of the iditarod trail invitational ultra-marathon is about 1.6×106 meters. about how many times as long is the course of the iditarod trail ultra-marathon as that of the boston marathon?

The ultra-marathon Idita Rod Trail is about 38 times longer than the Boston Marathon.

Step-by-step explanation:

Let

x -----> the length of the Boston Marathon in meters

y -----> the  length of the Idita rod Trail Invitational ultra-marathon in meters

we have

we know that

To find out how many times as long is the course of the Idita rod Trail ultra-marathon as that of the Boston Marathon, divide the length of the Idita rod Trail Invitational ultra-marathon by the length of the  Boston Marathon

so

Remember that

To divide two numbers in scientific notation, divide their coefficients and subtract their exponents

therefore

The ultra-marathon Idita Rod Trail is about 38 times longer than the Boston Marathon.

your answer would be 10x - 1