To determine the type of sequence formed by the number of cupcakes on each tray, let's examine the amounts given:
- First tray: 4 cupcakes
- Second tray: 12 cupcakes
- Third tray: 36 cupcakes
- Fourth tray: 108 cupcakes
Now, let's look at the sequence:
- First term (a_1): 4
- Second term (a_2): 12
- Third term (a_3): 36
- Fourth term (a_4): 108
Next, let's identify the ratio of consecutive terms:
- \( \frac{a_2}{a_1} = \frac{12}{4} = 3 \)
- \( \frac{a_3}{a_2} = \frac{36}{12} = 3 \)
- \( \frac{a_4}{a_3} = \frac{108}{36} = 3 \)
Since the ratio between each pair of consecutive terms is constant and equal to 3, this sequence is a geometric sequence with a common ratio of 3.
Thus, the sequence of cupcakes on the trays is a geometric sequence.