The seconds will be counted from the flash of the lightning till the sound of the thunder. The sounds travel about 1100 to 1200 feet/sec. Here the default will be 1150. Here the lightning distance is calculated as per the sound.
A flash of light in the sky caused by an electrical discharge between clouds or between a cloud and the Earth's surface is called as lightning. The flash heats the air and usually causes thunder. Lightning may appear as a jagged streak, as a bright sheet, or in rare cases, as a glowing red ball.
Calculate the lightning distance
Time From Flash To Thunder: 1125 seconds
Speed Of Sound In Air: 1100 meter/sec
Lightning Distance = 1237500 meter