SI unit (square and cubic)

 

Sloved questions on SI unit

questions on SI unit (VI)

 1. Pema rode 3 kilometers on his bike. his sister Sonam rode 2500 meters on her bike. Who rode the farthest and by how much more (answer in km)?

Ans:  Pema rode 3 km

          Sonam rode 2500 m                 we know 1km = 1000 m

                                                                            2500m = 2500 ÷ 1000

                                                                                          = 2.5 km

           since 3km is greater than 2.5km, Pema rode farthest by 0.5km (3 - 2.5 = 0.5)

2. Dawa is measuring two-line segments. The first line segment is 30 cm long. The second line segment is 500 mm long. How long are the two-ling segments put together? (answer in cm)

Ans: first line segment = 30 cm

         second line segment = 500 mm                        

                                                            we know 1cm = 10 mm

                                                                            500 mm = 500 ÷ 10

                                                                                          = 50 cm

            when two line segments put together:    30 cm + 50 cm =  80 cm

3. Penjor wants to send a box of oranges to a friend by mail. The box of oranges cannot exceed a mass of 5 kg. If each oranges has a mass of 200 g, what is the maximum number of oranges she can send?

Ans:  each oranges has a mass of 200 g. 

           box of oranges cannot exceed 5 kg. 

                                          convert 200 g to kg

                                           we know 1 kg = 1000 g

                                                            200g = 200 ÷ 1000

                                                                      = 0.2 kg

             since each oranges is 0.2 kg, Penjor can send 25 oranges. (5 ÷ 0.2 = 25)

4. Tashi grew 10.5 centimeters in 1 year. He is now 1.6 m tall. How tall was Tashi 1 year ago? (answer in cm)

Ans: Tashi grew 10.5 cm each year

         Present height = 1.6 m  (convert 1.6 m to cm)

                                  we know 1 m = 100 cm

                                                  1.6 m = 1.6 x 100

                                                            = 160 cm 

              Tashi's height 1 year ago:  160 cm - 10.5 cm

                                                         = 149.5 cm tall

5. Wangmo has a glass that can hold 250 ml of water. If she wants to fill a jug which can hold 2 litres of water, how many glasses of water does she need to fill the jug to the brim?

Ans: capacity of jug is 2 litres 

         capacity of glass is 250 ml  (convert 250ml to l)

                                                    we know 1L = 1000 ml

                                                                    250ml = 250 ÷ 1000

                                                                               = 0.25 L 

            to fill the jug to the brim: 2 ÷ 0.5 = 8

           therefore, Wangmo needs 8 glasses of water to fill the jug to the brim. 

6. Penjor walks 500 m every day. How many kilometers does he walk in a week?

Ans: Penjor walks 500 m per day.

                                     convert 500 m to km

                                     we know 1 km = 1000 m 

                                                     500 m = 500 ÷ 1000 = 0.5 km (1 day)

           in a week he walks: 0.5 x 7    (7 days in a week)

                                            = 3.5 km