At a certain time of day 1.8m tall person standing next to the washington monument cast a 0.7m shadow at the same time the washington monument cast a 65.8m shadow how tall is washington monument ‍♀️

169 m

Step-by-step explanation:

See the image below.

Line AB represents the monument and line BC its shadow

Line DB represents the man and Line BE it shadow.

The Sun’s rays are parallel, so AC||DE.

Then ∆ABC ~ ∆DBE

AB:BC::DB:BE

x/65.8 = 1.8/0.7     Multiply both sides by 65.8

       x = 65.6 × 1.8/0.7  

       x = 65.6 × 2.571

       x = 169 m

The height of the Washington monument is 169 m.