To calculate elapsed time use the equation:

Time = distance divided by velocity.

Velocity is normally given in terms of distance divided by time, as in
miles per hour or feet per second. The one obvious exception to this is knots which are nautical miles per hour. To calculate time, the units must be consistent. For example, if the speed is given in terms of miles per hour (MPH) then the distance must be given in miles.

Excel calculates time as fractional parts of a day, so if the velocity contains an hours unit, you divide the distance by the speed, and then divide the result by 24 (the number of hours in a day). If the velocity contains a seconds unit, you divide the distance by the speed, and then divide the result by 86,400 (the number of seconds in a day).

After the fractional part of a day is calculated, you can format cells to change the data to read as hours, minutes, and seconds.

You can use the steps in the following examples to calculate elapsed time.

#### Example 1: Miles Per Hour

- Start Excel and create the following spreadsheet:
A1: Distance B1: MPH C1: Time
A2: 50 B2: 65 C2:
A3: 100 B3: 55 C3:
A4: 2000 B4: 75 C4:

- In cell C2, enter the following equation:
=A2/B2/24

so that the spreadsheet now appears as:A1: Distance B1: MPH C1: Time
A2: 50 B2: 65 C2: 0.03
A3: 100 B3: 55 C3:
A4: 2000 B4: 75 C4:

- Select cell C2.
- On the
**Format** menu, click **Cells**. - On the
**Number** tab, under **Category**, select **Time**. - Under
**Type**, select **37:30:55**. - Click
**OK**.

The spreadsheet now appears as:A1: Distance B1: MPH C1: Time
A2: 50 B2: 65 C2: 0:46:09
A3: 100 B3: 55 C3:
A4: 2000 B4: 75 C4:

- Select cell C2 and drag to fill to cell C4.

The spreadsheet now appears as:A1: Distance B1: MPH C1: Time
A2: 50 B2: 65 C2: 0:46:09
A3: 100 B3: 55 C3: 1:49:05
A4: 2000 B4: 75 C4: 26:40:40

#### Example 2: Feet Per Second

- Start Excel and create the following spreadsheet:
A1: Distance B1: FPS C1: Time
A2: 60 B2: 60 C2:
A3: 6000 B3: 70 C3:
A4: 600000 B4: 80 C4:

- In cell C2, enter the following equation:
=A2/B2/86400

so that the spreadsheet now appears as:A1: Distance B1: MPH C1: Time
A2: 60 B2: 60 C2: 0.00
A3: 6000 B3: 70 C3:
A4: 600000 B4: 80 C4:

- Select cell C2.
- On the
**Format** menu, click **Cells**. - On the
**Number** tab, under **Category**, click **Time**. - Under
**Type**, select **37:30:55**.
- Click
**OK**.

The spreadsheet now appears as:A1: Distance B1: MPH C1: Time
A2: 60 B2: 60 C2: 0:00:01
A3: 6000 B3: 70 C3:
A4: 600000 B4: 80 C4:

- Select cell C2 and drag to fill to cell C4.

The spreadsheet now appears as:A1: Distance B1: MPH C1: Time
A2: 60 B2: 60 C2: 0:00:01
A3: 6000 B3: 70 C3: 0:01:26
A4: 600000 B4: 80 C4: 2:05:00