Alonso brings $21 to the market to buy eggs and avocados. He gets eggs that cost $2.5. Then he notices that the store only sells avocados in bags of 3 for $5. He wants to buy aS many avocados as he can with his remaining money. What is the largest number of avocados that Alonso can afford

Step-by-step explanation:

21≤2.50+5s subtract 2.50 from both sides

18.50≤5s  divide by 5

s≥3.7  he can buy up to 3 bags at $5 each

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.