Find the surface of the composite figure

Could someone help?

If there are four friends then each would get, 1.25 or 1 1/4. so this is how i solved 5 ÷ 4 = 1.25 . hope this ; )

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step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

1 the 1st term, 3 the 2nd term, 6 the 3rd term,etc.

note the following:

from the 1st term (1) to the 2nd term (3), we go up by 2,from the 2nd term (3) to the 3rd term (6), we go up by 3from the 3rd term (6) to the 4th term (10), we go up by 4, andfrom the 4th term (10) to the 5th term (15), we go up by 5.

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

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In order to find the price per bar, we divide the price by the amount of bars.   for the first one: 15.37/10 = $1.54 per barthe second package: 15.35/12 = $1.28 per bar.the 10-pack costs $1.54 per bar and the 12-pack costs $1.28 per bar.   the 12-pack has the better price per bar.now, let's look at the price per ounce.   we do this in a similar way.   we find the total amount of ounces in the package, and divide the price by the number of ounces.in the first package, we multiply 10*2.1=21.   we have 21 ounces in the first package.   now we divide 15.37/21.   in the first package, we have 0.73 dollars per ounce.now, let's look at the second package.   we start by multiplying 1.4*12=16.8.   there are 16.8 ounces in the package.   now, we divide 15.35/16.8=0.91.   so, in the second package, we have 0.91 dollars per ounce.the cost per ounce of the 10-pack is $0.73 and the cost per ounce of the 12-pack is $0.91.   the first package has the better price per ounce.the better explanation is the second one, because i prefer the lower price per ounce, i think that the 1st pack is the better buy.