The pebble's total splash width is 1.5 meters because 6 times 1/4 equals <<6*1/4=1.5>>1.5.
The rock's total splash width is 1.5 meters because 3 times 1/2 equals <<3*1/2=1.5>>1.5.
The boulder's total splash width is 4 because 2 times 2 equals four.
The total splash width for all the rocks is 7 because 1.5 plus 1.5 plus 4 equals 7.
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