Add the Same Amount to Selected Numbers:

You may want to increase all the numbers in a range by a set amount. For example, in this price list, all the prices should be increased by $1.50. The following technique makes it easy to increase the prices, all at once.
1. In a blank cell, enter the amount of the increase. In this example, 1.50 was entered in cell D2
2. Copy the cell which contains the increase amount.
3. Select the cells which contain the amounts that you want to increase. Here, cells B2:B5 are selected.
4. On the menu bar, click Edit | Paste Special
5. Click Values, and click Add, then click OK.
6. Each of the selected numbers is automatically increased by $1.50