Lesson 4 Estimating Distance - Grade 3 Mathematics

Mathematics 人教版三年级数学上册 for Grade3,Part1,People’s Education Press Measurement Lesson 4: Estimating distance  Review introduction What units should be used to measure...

Mathematics 人教版三年级数学上册 for Grade3,Part1,People’s Education Press Measurement Lesson 4: Estimating distance  Review introduction What units should be used to measure the following lengths? The length of the railway line from Thickness of Length of Length of Bangkok to triangle ruler swimming box Chiangmai pool Decime kilomet millimete met er r er ter  New course exploration 6 Estimate how far it is from your home to school. It takes me about 200 steps to I took the bus for 3 walk 100 meters. From home to stops, each stop was school, I walk 600 steps, about about 500 meters, so it 300 meters. was about 1500 meters away. It takes me about 2 minutes to walk 100 meters. It takes me about 10 minutes to walk from home to school, which is about 500 meters. Step count estimation Site method It takes me about 200 steps estimation I took themethod to walk 100 meters. From bus for 3 home to school, I walk 600 steps, about 300 meters. stops, each stop was about 500 meters away, so the total distance was about 1500 meters. It takes me about 2 minutes to walk 100 meters. It takes me Time estimation about 10 minutes to walk from method home to school, which is about 500 meters.  How do you estimate? Metho How many steps are d1 100 meters is about 200 steps there in 100 meters? How many steps from It's about 600 steps from home to school. home to school? How many meters from There are 3 sections of 200 home to school? and 300 meters in 600 miles.  Metho d2 How many stops are there There are 3 stops from home to school from home to school? How far is the distance There is 500m between the two stations. between the two stations? How many meters from 3 times 500 is 1500, 1500m. home to school?  meth od3 How long does it take to About 2 minutes walk 100m? How long does it take to get from home to 10 minutes school? How many meters Among the 10, 5 are 2 from home to minutes and 500 meters. school? In-class exercises 1. Estimate the length and width of the classroom. Tip: It is most convenient to use step length estimation. 2. Estimate how far it is from your home to the nearest store. Tip: You can use the number of steps you walk to estimate, or you can use 3. How far is it from their homes to school? (Make a connection) It takes me I take 2 steps about 2 I took the bus which is about minutes to home for 4 stops, 1m, so after walk 100m. and each two After school, it school I walked takes me 20 stops were about about 800 minutes to 500m apart. steps to get walk home. home. 400 1k 2k m m m  Talent Training 1. How long does it take to travel 1 km using different modes of transportation? Estimate Estimate and connect. 15minutes 30 seconds 5seconds 5minutes 2. Aunt Lia rides an electric bike from home to work at the supermarket every day. It takes her 10 minutes to get there. If the electric bike travels about 600 m per minute, how many kilometers is Aunt Lia's home from the supermarket? 600+600+…+600= 6000(m)=6 (km) Add 10 time of 600 Answer: Aunt Lia’s home is about 6km away from the supermarket.  Class summary When estimating longer distances, the distance of a few steps, the distance walked in one minute, or the distance of a bus stop can all be used as unit lengths to estimate the total length of the distance.  Homew ork 1. Choose from the after-class exercises; 2. Complete the exercises in the workbook for this lesson. 人教版三年级数学上册 CLASS IS OVER!