To find the number of claps in 30 seconds, we can set up a proportion using the given information:
28 claps / 12 seconds = x claps / 30 seconds
To solve this proportion, we can cross-multiply and then divide:
28 * 30 = 12 * x
840 = 12x
Now, divide both sides of the equation by 12:
840 / 12 = x
70 = x