Area of a square Formula Length x Width

Area of a square � Formula: Length x Width

Area Calculating the area of an even boundary � A map with a scale of 1: 50 000. The length of this map is 5 cm and the width is 3 cm. Calculate the area represented by the map. � *Convert the length and width into what they represent in reality before using the formula*.

Area Calculating the area of an even boundary � Scale 1: 50 000 - therefore each cm on the map represents 0. 5 km in reality � Length: 5 cm x 0. 5 km = 2. 5 km Width: 3 cm x 0. 5 km = 1. 5 km � Area = Length x Width = 2. 5 km x 1. 5 km = 3. 75 sq. km

Area Calculating the area of an even boundary � Get out the map of Houston � Calculate the area of Klinger Lake.

Area Calculating the area of an even boundary Step 1: Work out the area of one grid square on the map. � Scale of this map: 1: 50 000, therefore each cm represents 0. 5 km � Length: 2 cm x 0. 5 km = 1. 0 km � Width: 2 cm X 0. 5 km = 1. 0 km � Area of One Grid Square = 1. 0 km x 1. 0 km = 1. 0 sq. km

Area Calculating the area of an even boundary � Step 2: Determine the number of squares that the object occupies. � Klinger Lake occupies a total of about 0. 5 of a grid square.

Area Calculating the area of an even boundary � Step 3: Multiply the number of grid squares that the object occupies by the area of one grid square. � Hence, 0. 5 of a square x 1. 0 sq. km = 0. 5 sq. km which is the area of Klinger Lake.

Area Calculating the area of an even boundary � Using the map of St. John's, Newfoundland & Labrador. � Calculate the area of the built up portion of the city (i. e. the pink shaded area).

Area Calculating the area of an even boundary � Step 1: Work out the area of one grid square on the map. � It is the same as the previous map: 1. 0 sq. km.

Area Calculating the area of an even boundary Step 2: Determine the number of squares that the object occupies. � In this situation, one could go from grid square to grid square determing how much the built up area occupies each square. � � i. e. 0. 1 of a grid square (5866) + 0. 4 (5966) + 0. 7 (5967) + 0. 7 (6067) + 0. 03 (5868) + 0. 5 (5968) + 1. 0 (6068) + 0. 25 (6168) + 0. 2 (5869) + 0. 6 (5969) + 1. 0 (6069) + 0. 85 (6169) + 0. 2 (6269) + 0. 8 (6070) + 0. 85 (6170) + 0. 2 (6270) + 0. 2 (6071) + 0. 4 (6171) = 8. 98 squares

Area Calculating the area of an even boundary � Step 3: Multiply the number of grid squares that the object occupies by the area of one grid square. � Hence, 8. 98 squares x 1. 0 sq. km = 8. 98 sq. km which is the area of downtown St. John's. Note: Clearly, there is an acceptable range for the answer due to measuring error.

Area Assignment Work 1) Using the map of St. John's, determine the area of Quidi Vidi lake. 2) Determine the area of Long Pond. 3) Determine the area on the map south of Blackhead Road and east of Maddox Cove Road.

Area Practice Questions 1) The area of one grid square on this map is 1. 0 km 2. � If you were to move all the parts of Quidi Vidi Lake into one square, you will find that it does not occupy one complete grid square but rather about 0. 5 of a grid square. If you are having trouble visualizing this, picture the square as if it was divided into quarter sections and move pieces of the lake into those sections. � Therefore, the area of Quidi Vidi Lake is 0. 5 of a square x 1. 0 km 2 = 0. 5 km 2. � �

Area Practice Questions � 2) Again, the area of one grid square is 1. 0 km 2. � Picture the grid square divided into quarters. Ask yourself, would Long Pond occupy half of a grid square? No. How about one quarter of a grid square? Perhaps. Acceptable range: 0. 2 to 0. 25 of a grid square. � Therefore the area of Long Pond is 0. 2 x 1. 0 km 2 = 0. 2 km 2 � Acceptable Range: 0. 2 km 2 to 0. 25 km 2 �

Area Practice Questions 3) Again, the area of one grid square is 1. 0 km 2. The area south of Blackhead Road and east of Maddox Cove Road occupies: � 0. 1 (6162) + 0. 9 (6262) + 1. 0 (6362) + 1. 0 (6462) + 1. 0 (6562) + 1. 0 (6662) + 0. 3 (6762) + 0. 35 (6263) + 0. 35 (6363) + 0. 65 (6463) + 1. 0 (6563) + 1. 0 (6663) + 0. 35 (6763) + 0. 05 (6464) + 0. 5 (6564) + 0. 2 (6664) + 0. 08 (6764) = 9. 83 squares � Therefore, the area is 9. 83 squares x 1. 0 km 2 = 9. 83 km 2. � Acceptable Range: 9 km 2 to 10. 5 km 2 � � �