**Answer and explanation:**

**To find : **Calculate to the nearest 1/10th meter the length of the side of a 7th, 12th, and 30th hectare square plot.

**Solution :**

**The area of the square is given by, **

where s is the side length.

**We know,**

**1) **The area of square plot is 7 hectare.

**Area in meter square is **

**Substitute the value in the formula,**

**Side nearest to 1/10th meter is 264.8 meter.**

**2) **The area of square plot is 12 hectare.

**Area in meter square is **

**Substitute the value in the formula,**

**Side nearest to 1/10th meter is 346.4 meter.**

**3) **The area of square plot is 30 hectare.

**Area in meter square is **

**Substitute the value in the formula,**

**Side nearest to 1/10th meter is 547.7 meter.**