We will use the following statement:

If the scale factor (ratio between linear measurements of two similar figures) is a:b, the:

(1) the ratio between any area measurements of those two similar figures will be a^2:b^2 and

(2) the ratio between any volume measurements of those two similar figures will be a^3:b^3

Son in our case we have:

a^3 : b^3 = 1728 : 4913

a^3 : b^3 =12^3 : 17^3

Let A2 represent the area of the large pyramid and A1 = 2880 the area of the small pyramid than we have:

A1 : A2 = 12^2 : 13^2

2880 : A2 = 12^2 : 13^2

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click here to see the equation solved for A2

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A2 = 6760

The area of the large pyramid is 6760.