Distance Firework B would have traveled after 0.25 seconds:
240 x 0.25 = 60 feet
Let x be the time that it will explode together:
60 + 240x = 340x
100x = 60
x = 60 ÷ 100
x = 0.6 sec
Firework A will explode at 0.6 seconds after it is launched
Firework B will explode at (0.6 + 0.25) 0.85 seconds after it is launched.
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Answer: Firework B will explode at 0.85 seconds after it is launched.
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