Question

Estimate the weight of 6 apples.

Answer 1

The answer:  1533 g {"grams"} ;  or even "1530 g" or "1500 g" ; would be an acceptable estimate.
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Note:  We are asked to:  "Estimate the weight of 6 (six) apples."

Given: (from the table—within the image attached):  
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"2 apples weigh "511 g" ; 


"then "6 apples" would weigh about 3 times that weight;  since: 

  "2 apples;  multiplied by "3" , is "6 apples" .

so:  "511 g * 3 ≈  500 g * 3 = 1500 g ". 

or:  
"511 g * 3 ≈ 510 g * 3  = (500 g * 3)  + (10 g * 3) = (1500 + 30) g = 1530 g. 

or:   

"511 g * 3 ≈ 511 g * 3  = (500 g * 3)  + (11 g * 3) = (1500 + 33) g = 1533 g.
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Note:  The table shows that the given numbers of apples, along with their respective weights, are not [evenly and equally] proportional —reflecting the fact that there is variation among weight in apples across the board.
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