In a hundredths grid - square In a hundredths grid, there are 10 blocks in each column. 10/100 = 10%. So one column is equal to 10%. In a tenths grid- square In a tenths grid, there is one block in each column. So 1/10 blocks = 10%. 10/100 can simplify into 1/10. This is why both grids are equal. They are both equivalent fractions. Both grids have columns that equal 10%.