A geometry class in the second part of the charming movie of Anne of Green Gables 1985.
Wikipedia:
"Both parts of the film were among the highest-rated programs
of any genre ever to air on a Canadian television network"
About the Book:
more than 50 million books have been sold.
In the geometry class scene, one sees a triangle with sides 1000 and 1600. The teacher
gives as the hypothenuse 1900. Not a bad approximation. In reality it is the square root of
10002+16002= 1886.8. One can indeed get this without a calculator. First divide by 100
then compute the square root of 102+162 = 356 and then notice that this is close to
192=361. Finally multiply 19 again with the scaling factor 100.