The expression is probabily more clear if written as
[tex] 27 \times 1.2^4 [/tex]
The second factor, [tex] 1.2^4 [/tex], is a power, which is a short way of writing multiplication of a number times itself: the exponent tells you how many times you have to multiply the base by itself:
[tex] 1.2^4 = 1.2\cdot 1.2\cdot 1.2\cdot 1.2 [/tex]