Laura has $730 in savings. She spends 10% of her money on a phone. How much money does she spend?

She spended #10%# of her savings, that can also be said as per every $100 she had, she spended $10 of them.
This can be written as
#73cancel0xx(1cancel0)/(1cancel0cancel0)=x#
Where #x# is the money spended in phone
#73=x#
She spended $73 on her phone

We can rewrite this problem as:

What is 10% of $730?

"Percent" or "%" means "out of 100" or "per 100", Therefore 10% can be written as #10/100#.

When dealing with percents the word "of" means "times" or "to multiply".

Finally, lets call the amount of money we are looking for "m".

Putting this altogether we can write this equation and solve for #m# while keeping the equation balanced:

#m = 10/100 xx $730#

#m = ($7300)/100#

#m = $73.00#

Laura spent $73.00

#"to calculate "10%" of a quantity"#

#color(blue)"per cent means out of 100"#

#rArr10%=cancel(10)^1/cancel(100)^(10)=1/10larr"in simplest form"#

#"thus "10%" means divide the quantity by 10"#

#rArr10%" of "$730=$730-:10=($730)/10=$73#

#"Laura spends "$73.00" on her phone"#

In the beginning, she has #$730#

Now we should understand what #10%# is. #10%# means #10 # parts of #100# parts , that is:

#color(blue)(10/100#

Now, we multiply it with the total savings

#rarr730xx(10)/(100)#

#rarr7300/100#

#rarr(73cancel(00))/(1cancel00)#

#rArrcolor(green)($73#

So, she spends #$73# on her phone

Hope that helps!!! ☺☻