Sam can cut 3/4 sq ft of grass in 1 hour. So, to cut 1 square feet the nuber of hours taken is
[tex]\begin{gathered} \frac{3}{4}sq\text{. ft}\longrightarrow1\text{ hour} \\ 1sq\text{. ft}\longrightarrow\frac{4}{3}\text{hours} \end{gathered}[/tex]There is total 5 sq ft. To cut 5 sq ft, the number of hours taken is
[tex]\begin{gathered} 5\ast\frac{4}{3}\text{hours}=\frac{20}{3}=6.66\text{hours}\cong6.7\text{hours} \\ In\text{ 6.6}6\text{ , 6 is the next number to the first digit after decimal. } \\ As\text{ 6 is greater than 5, we add 1 to the digit after the decimal. } \\ So,\text{ the digit after the decimal, which is }6,\text{ is increased to 7.} \\ So\text{ 6.66 is appro}\xi mated\text{ to }6.7\text{.} \end{gathered}[/tex]It will take 6.7 hours to cut 5 sq ft grass.
