Jane is going to fence in her back yard. she has bought 100 feet of fencing and knows that she wants to fence in a rectangular area where one side will be the back of her house. she knows her house if 30 ft across the back. which of the following is the equation that jane can use to figure out how far back from the house she can fence in?
a) 30(x+30) = 100
b) 30x = 100
c) x+x+30 = 100
d) x+30 = 100

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.