Problem:

Listed in cells B1:E2 are several destinations and their hourly time difference with New York.
We want to convert the time value in cell B3 (New York local time) to the equivalent local time in each destination city.

Solution:

With destinations in cells C1:E1 and time differences in cells C2:E2, enter the following formula in cell C3, and copy across to cell E3:
=$B$3+(C2/24)*-1