How do you estimate #41 times 58# by rounding?

Question

2300 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-11-20T09:36:59

#41xx58 ~~ 40xx60 = 2400#

Rounded to the nearest #10# we have:

#41 ~~ 40#

#58 ~~ 60#

So:

#41 xx 58 ~~ 40 xx 60#

To multiply #40# and #60# we just need to multiply #4xx6# then add #2# zeros:

#40xx60 = (4xx10)xx(6xx10)#

#color(white)(40xx60) = 4xx6xx10xx10#

#color(white)(40xx60) = 24xx100#

#color(white)(40xx60) = 2400#

So

#41xx58~~40xx60=2400#

Actually:

#41xx58 = 2378#

which to the nearest #100# is #2400#