Page:The Rhind Mathematical Papyrus, Volume I.pdf/109

53]

Problem 52

Example of a cut—off (truncated) ''triangle of land. Suppose it is said to thee, What is the area of a cut-off triangle of land of'' 20 khet in its side, 6 khet in its base, 4 khet in its cut—off line?

Add its base to its cut-off line; it makes 10. Take $1/undefined$ of 10, that is 5. in order to get its rectangle. Multiply 20 times 5; it makes 10 (10 ten-setat). This is its area.

Do it thus:

Its area is 100 setat (10 ten-setat).

Problem 53

Areas of sections of a triangle.