Aclub decides to sell t-shirts for $15 as a fundraiser. it cost $20 plus $9 per t-shirt to make the t-shirts. write and solve an equation to find how many t-shirts the club needs to make and sell in order to profit at least $152?
a. 15x - (9x+20) greater than or equal to 150; x greater than or equal to 28.33
b. 15x-9x + 20 greater than or equal to 150; x greater than or equal to 20
c. (8x+20) -15x greater than or equal to 150; x greater than or equal to 20
d. 15x -9 (x+20) greater than or equal to 150; x greater than or equal to 20

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.