Question

Rita is riding in a bike race that goes through a valley and a nearby mountain range.
The table gives the altitude (in feet above sea level) for the five checkpoints in the race.
Use the table to answer the questions.
Checkpoint. Altitude
(feet above sea level)
1, -23
2. 2,109
3 -146
4 -194
5 1,375
(a) How much lower is Checkpoint 1 than Checkpoint 2?
X
ft lower
(b) The top of a hill rises 68 feet above Checkpoint 4.
What is the altitude of the top of the hill?

Answer 1

To solve the questions, we'll use the given altitudes of the checkpoints.

### (a) How much lower is Checkpoint 1 than Checkpoint 2?

**Altitude of Checkpoint 1:** -23 feet
**Altitude of Checkpoint 2:** 2,109 feet

To find out how much lower Checkpoint 1 is than Checkpoint 2, subtract the altitude of Checkpoint 1 from the altitude of Checkpoint 2:

\[
\text{Difference} = \text{Altitude of Checkpoint 2} - \text{Altitude of Checkpoint 1}
\]

\[
\text{Difference} = 2,109 - (-23)
\]

Since subtracting a negative is the same as adding, this becomes:

\[
\text{Difference} = 2,109 + 23 = 2,132 \text{ feet}
\]

So, Checkpoint 1 is **2,132 feet lower** than Checkpoint 2.

### (b) The top of a hill rises 68 feet above Checkpoint 4. What is the altitude of the top of the hill?

**Altitude of Checkpoint 4:** -194 feet

To find the altitude of the top of the hill, add 68 feet to the altitude of Checkpoint 4:

\[
\text{Altitude of the top of the hill} = \text{Altitude of Checkpoint 4} + 68
\]

\[
\text{Altitude of the top of the hill} = -194 + 68
\]

Calculating this gives:

\[
\text{Altitude of the top of the hill} = -126 \text{ feet}
\]

So, the altitude of the top of the hill is **-126 feet above sea level**.