(54+5)×2
=59×2
= 1 18 (cm)
The second binding method: arrange nine boxes in three layers to form a cuboid. Its width is 3× 6 = 18cm and its height is 5× 3 = 15cm.
( 18+ 15)×2
=33×2
=66 cm
100 >66
Therefore, the second binding method saves the most tapes.
Answer: The three-tier arrangement of 9 boxes is the most economical, with a minimum of 66 cm.
Extended data:
unit of measure
The speed of progress between length, area and volume, and their similarities.
Quality units and the progress between them
1 ton = 1000 kg = 1000 g.
Time unit exchange rate
1 hour =60 minutes 1 minute =60 seconds
1 = 10.
Ratio and proportion
We can use direct proportion, inverse proportion, simplified proportion, proportion calculation, proportion and fraction, division connection, proportion, proportion and ratio to solve application problems.
Graphics and space
Graph, space, perimeter, area, lateral area, surface area, graph transformation, graph and position, graph understanding and measurement.
Statistics and possibilities
Statistical table, statistical chart, average, median, mode, possibility
integer
Meaning of integer 1: … Numbers like -4, -3, -2,-1, 0, 1, 2, 3, … are called integers.
2 natural numbers: when we count objects, 1, 2, 3, 4 ... the numbers used to represent the number of objects are called natural numbers. There is no object, which is represented by 0, and 0 is also a natural number.
3 counting unit
One, ten, one hundred, one thousand, ten thousand, one hundred thousand, one million, ten million, one hundred million ... are all counting units.
The propulsion rate between every two adjacent counting units is 10. This counting method is called decimal counting method.
4 digits
Counting units are arranged in a certain order, and their positions are called numbers.
Divisibility of 5 numbers: the integer A is divisible by the integer B (b≠0), and the divisible quotient is an integer without remainder, so we say that A is divisible by B, or that B is divisible by A. ..
If the number A is divisible by the number B (b≠0), then A is called a multiple of B, and B is called a divisor of A (or a factor of A). Multiplication and divisor are interdependent.
Because 35 is divisible by 7, 35 is a multiple of 7, and 7 is a divisor of 35.
7. What is the ratio? The division of two numbers is called the ratio of two numbers. Such as: 2÷5 or 3:6 or 1/3.
The first and second items of the ratio are multiplied or divided by the same number at the same time (except 0), and the ratio remains unchanged.
8. What is proportion? Two formulas with equal ratios are called proportions. For example, 3:6=9: 18
9. Basic properties of proportion: In proportion, the product of two external terms is equal to the product of two internal terms.
10, solution ratio: the unknown term in the ratio is called the solution ratio. Such as 3:χ=9: 18.
Reference source: Baidu Encyclopedia-Primary Mathematics