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由面积求周长 = luas → sisi → perimeter 正方形面积 = 边长 × 边长，所以先想：哪一个数自己乘自己等于面积？那就是边长。知道边长以后，周长 = 四乘边长。 例子：面积 49 cm² 的正方形，边长 7 cm，周长 28 cm。 注意：面积的数字不能直接当周长；只乘二也只是两条边。

from area to perimeter = luas → sisi → perimeter The area of a square is side × side, so first ask which number times itself gives the area; that is the side. Then perimeter = 4 × side. Example: a square with an area of 49 cm² has 7 cm sides and a perimeter of 28 cm. Watch out: the area number is not the perimeter, and doubling the side covers only two sides.

铺草要几卷 = berapa gulung rumput 铺满是面积的问题：先算院子的面积（长乘宽），再看一卷草能铺多少平方米，用院子面积除以一卷的面积，就是需要的卷数。 例子：院子 10 m × 6 m = 60 m²，一卷铺 5 m²，要 60 ÷ 5 = 12 卷。 注意：面积本身不是卷数；绕院子一圈的长度和铺草无关。

how many rolls of grass = berapa gulung rumput Covering is an area problem: find the area of the yard (length × width), then divide by the area one roll covers to get the number of rolls. Example: a 10 m × 6 m yard is 60 m²; if one roll covers 5 m², you need 60 ÷ 5 = 12 rolls. Watch out: the area itself is not the number of rolls, and the distance around the yard has nothing to do with covering it.

水的体积 = isi padu air 水只装到一部分高度，所以水像一个比较矮的长方体：长和宽跟鱼缸一样，高要用水的高度，不是鱼缸的高度。体积 = 长 × 宽 × 水的高度。 例子：鱼缸 40 cm × 20 cm × 30 cm，水高 10 cm，水的体积 = 8 000 cm³。 注意：只乘长和宽得到的是底面积，还没乘高。

volume of water = isi padu air The water fills only part of the tank, so it forms a shorter cuboid: the same length and width as the tank, but the water's height instead of the tank's. Volume = length × width × water height. Example: a 40 cm × 20 cm × 30 cm tank with water 10 cm deep holds 8 000 cm³ of water. Watch out: length × width alone is only the base area.

比较两个容器 = banding dua bekas 分别算出两个容器的体积：长方体用长乘宽乘高，正方体用边长连乘三次。比较大小，再用大减小求差，单位是立方厘米。 例子：A 是 5 × 4 × 3 = 60 cm³，B 是 4 × 4 × 4 = 64 cm³，B 比 A 多 4 cm³。 注意：不能只比最长的一条边，要比整个体积。

comparing two containers = banding dua bekas Work out each volume: length × width × height for the cuboid, and the side three times for the cube. Compare them, then subtract the smaller from the bigger, in cubic centimetres. Example: A is 5 × 4 × 3 = 60 cm³ and B is 4 × 4 × 4 = 64 cm³, so B holds 4 cm³ more. Watch out: comparing only the longest edges is not enough; compare the whole volumes.

长多几米 = lebih panjang 先用题目的关系找出新的长：比原来长几米，就把原来的长加上那几米；宽没有变，还是原来的边长。最后用新的长乘宽求面积。 例子：正方形花圃每边 4 m，另一块比它长 3 m、宽一样，面积 = 7 × 4 = 28 m²。 注意：多出来的几米是加在长上，不是直接拿来乘。

how much longer = lebih panjang Use the relationship in the question to find the new length: add the extra metres to the old length. The width has not changed; it is still the old side. Then multiply the new length by the width. Example: a square bed has 4 m sides; another is 3 m longer with the same width, so its area is 7 × 4 = 28 m². Watch out: the extra metres are added to the length, not multiplied on their own.

由周长求面积 = perimeter → sisi → luas 绕一圈的长度就是周长。正方形四条边一样长，所以边长 = 周长 ÷ 4。知道边长后，面积 = 边长 × 边长。 例子：周长 28 m 的正方形场地，边长 7 m，面积 49 m²。 注意：周长的数字不是面积；边长要先除以四才对。

from perimeter to area = perimeter → sisi → luas The length that goes once around is the perimeter. A square's four sides are equal, so side = perimeter ÷ 4. Then area = side × side. Example: a square field with a perimeter of 28 m has 7 m sides and an area of 49 m². Watch out: the perimeter number is not the area; divide by 4 to get the side first.