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    Just part b question 8 and part c question 10.

    8). A squirrel is collecting nuts. It collects 5 on the first day of the month, 8 on the second, 11 on the third and so on in an arithmetic progression.
    a. How many nuts will it collect on the 20th day? (I found the answer to be 62 and checked it was right).
    b. After how many days will it have collected more than 1000 nuts. (I'm stuck on this).

    10). a. Find sum of natural numbers from 1-100 inclusive. (5050 which i checked was right)
    b. Find sum of natural numbers from 101 - 200 inclusive. (Which I found to be 15,050 and checked was right).
    c. Find and simplify an expression for the sum of the natural numbers from n + 1 to 2n inclusive.

    Can anyone help please?
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    (Original post by Rainbow-Dream)
    b. After how many days will it have collected more than 1000 nuts.
    \frac{n}{2}(2a+(n-1)d)>1000
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    8.b) You know a, d and S, so, if you use an appropriate formula for the sum of an AP, then that should give you a quadratic to solve for n.
    10. c) You've effectively already done that in b). So just use "n+1" as a, and "2n" as L, and see where that gets you, with "1" as the common difference, and see where that gets you.
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    (Original post by Revolution is my Name)
    8.b) You know a, d and S, so, if you use an appropriate formula for the sum of an AP, then that should give you a quadratic to solve for n.
    10. c) You've effectively already done that in b). So just use "n+1" as a, and "2n" as L, and see where that gets you, with "1" as the common difference, and see where that gets you.

    oohhh thanks.
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    (Original post by Pheylan)
    \frac{n}{2}(2a+(n-1)d)>1000
    thanks.
 
 
 
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