Suppose that all blocks in a city are the same length. Streets run north and south. They are numbered consecutively, starting with First Street. Avenues run east and west. They are also numbered consecutively, starting with First Avenue.

Jerome Walker lives at the corner of Third Street and Twenty-Fourth Avenue. He walks to the bank at Third Street and Eleventh Avenue, to the post office at Tenth Street and Eleventh Avenue, and then to the barbershop on Tenth Street and Twenty-Fourth Avenue. Then Jerome Walker walks home.

How many blocks does Jerome Walker walk?

40 blocks

Step-by-step explanation:

Imagine the city is placed on a Cartesian plane grid or graph. The streets count rightwards and avenues count upwards.

Each location can be written as a coordinate or ordered pair in the form (x, y). "x" is the street number and "y" is the avenue number.

Jerome Walker lives at 3rd St. and 24th Ave. He lives at (3, 24).

The bank at 3rd St. and 11th Ave. is at (3, 11).

The post office at 10th St. and 11th Ave. is at (10, 11).

The barbershop at 10th St. and 24th Ave. is at (10, 24).

And again, his home is at (3, 24).

Calculate the number of blocks, or squares on the grid, between each part of his walk. Then, add the numbers together.

(3, 24) to (3, 11) : 24-11 = 13

(3, 11) to (10, 11) : 10-3 = 7

(10, 11) to (10, 24) : 24-11 = 13

(10, 24) to (3, 24) : 10-3 = 7

13 + 7 + 13 + 7 = 40

Therefore Jerome Walker walked 40 blocks.