**Length Unit Conversion **– Because previously there has been a clarification of the material about **Weight Unit Conversion Ladder in Mathematics**, so this time we continue the material that is still working together, namely the discourse on the conversion of weight units that are commonly used in daily activities. It’s the same as a sequence of units of weight, each unit of length is written in a sequential ladder where if we want to convert a unit into a unit that is one level below it, we must multiply it by 10. Meanwhile, if we want to change a unit of length into another unit that is one level above it, then we must divide the value by 10. This conversion ladder is formed so that it is easier for us to remember and carry out conversions or changes in values between units at one level to another level. The following is an image of the sequence of units of length in mathematics:

1 km |
10 hm |

1 km |
1000 m |

1 km |
100000cm |

1 km |
1000000mm |

1 m |
100 cm |

1 m |
0.1 dam |

1 m |
0.001 km |

1 m |
10 dm |

1 m |
1000mm |

Let’s continue by observing some pattern questions regarding the following length unit material:

**Example question 1** Sweet mother has a mango tree with a height of 12 dm. One time he cut the top of the tree so that the height of the mango tree was reduced by 20 cm. Then, a new shoot grows which causes the tree to grow 30 mm tall. So, how tall is sweet mother’s mango tree now?

**Solution:** First, equate the units to centimeters.

12 dm – 20 cm + 30 mm = 120 cm – 20 cm + 3 cm = 103 cm

**Example question 2** PT Jalan Bagus has completed a 13 km road asphalting project. Two sections of the road that have been paved successively are 350 dams and 4,500 m long. So how far is the unpaved road?

**Solution:** First, equate the units to meters

13km – 350 dam – 4500 m = 13000 m – 3500 m – 4500 m = 5000 m

**Example questions 3** A construction worker connects three wooden blocks 95 cm, 15 dm, and 5 m long. So what is the length of the three wooden blocks after being joined?

**Solution:** Equate the units to centimeters.

95 cm + 15 dm + 5 m = 95 cm + 150 cm + 500 cm = 745 cm

**Example question 4** Gilang bought a 20 m long rope. Then he cut the rope 30 dm long to be used as a clothesline. Then he cut the rope again as long as 500 cm to be used as a goat rope. Then the remaining rope that is owned by Gilang now is?

**Solution:** Equate the units to centimeters

20m – 30 dm – 500 cm = 2000 cm – 300 cm – 500 cm = 1200 cm

**Example questions 5** An athlete has run 3 km over 600 m, then he runs another 8.5 dam. How far has the athlete covered?

**Solution:** Equate the units in meters.

3 km over 600 meters = 3600 meters

8.5 dam = 85 m

Then the distance that has been traveled is 3600 m + 85 m = 3685 m

How? after reading the material and pattern of questions about *Ladder Conversion of Units of Length in Mathematics *Do you understand more about the units of length that are often used in mathematical calculations? Keep practicing by doing other exercises related to this material. Good luck.