There was an equal number of benches and tables in the morning. At 1 p.m., some benches were added and some tables were removed, resulting in the number of benches being increased by 20% while the number of tables decreased by 30%. At 9 p.m. the number of benches increased by 50%. If a total of 64 benches were added during the day, how many more benches than tables were there in the end?

At 1 p.m.	Benches	Tables
Before	1 u	1 u
Change	+ 0.2 u	- 0.3 u
After	1.2 u	0.7 u

At 9 p.m.	Benches	Tables
Before	1.2 u	0.7 u
Change	+ 0.6 u	No change
After	1.8 u	0.7 u

Number of benches added
= 20% x 1 u
= ²⁰₁₀₀ x 1 u
= 0.2 u

Number of tables removed
= 30% x 1 u 
= ³⁰₁₀₀ x 1 u
= 0.3 u

Number of benches increased by benches at 9 p.m.
= 50% x 1.2 u
= ⁵⁰₁₀₀ x 1.2 u
= 0.6 u

Number of benches added during the day
= 1.8 u - 1 u
= 0.8 u

0.8 u = 64

1 u = 64 ÷ 0.8 = 80

Number of more benches than tables in the end
= 1.8 u - 0.7 u
= 1.1 u
= 1.1 x 80
= 88

Answer(s): 88