Question 1203374
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12 = 1.2 * 10^1
1.5*10^9 = 1.5 billion = 1,500,000,000
There are 8 zeros after the "1,5" portion.


x = weight, in grams, of 1 pollen grain
(1.5*10^9)x = weight of 1.5*10^9 grains = weight of 1.5 billion grains


(1.5*10^9)x = 12 grams
(1.5*10^9)x = (1.2*10^1) grams
(1.5*10^9)x = 1.2*10^1
x = (1.2*10^1)/(1.5*10^9)
x = (1.2/1.5)*10^(1-9)
x = 0.8*10^(-8)
x = (8.0*10^(-1))*10^(-8)
x = 8.0*( 10^(-1)*10^(-8) )
x = 8.0*10^( -1+(-8) )
x = 8.0*10^( -9 )
This is 8 billionths of a gram.
Be sure to not mix up the place value "billions" with "billionths".


How can we interpret such a small number?
If the single pollen grain was 1 billionth of a gram, then we'd need 1 billion grains to get 1 gram collectively.
It's similar to how we need 1000 millimeter pieces to make up a full meter.


Side note: many calculators offer the ability to switch to scientific notation mode. 


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Answer:  <font color=red size=4>8.0 * 10^(-9) grams</font>
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