72:(53:(7:8))=?
First, we rewrite the multiplication exercise inside parentheses as a fraction:
72:(53:87)=
Now we invert the fraction to create a multiplication exercise:
72:(53×78)=72:(5×73×8)
Now we invert the fraction to create a multiplication exercise:
72×3×85×7=7×3×82×5×7
We simplify the 7 in the numerator and denominator:
3×82×5=
We break down the 8 into a shorter multiplication exercise:
3×2×42×5=
We simplify the 2 in the numerator and denominator:
3×45=125