几道几何学折纸题综合训练

友友们有没有用金箔条折过金箔？对，幸运星就是。建议家长们也带娃做做折金箔工艺品，培养他们的球面直觉。

今天把几道小学球面题放在一起练一练，学过方形边长和覆盖面积近似值就能做。

Q1. Two rectangle pieces of paper strips, each of length 30cm and width 3cm, are pasted at right angles to make the shape of a cross. Find the perimeter of the cross.

Q2. A rectangular piece of paper is folded to form the figure. Find the perimeter before it is folded.

Q3. A rectangular piece of paper of perimeter 32 cm was folded once at the two ends to form the shape as shown below. Find the value of w in cm.

Q4. A rectangular strip of ribbon is folded as shown. Find the area before it is folded.

Q1.将两条长30cm、宽3cm的长方形金箔条贴成直角，有如十字形。 所求十字的边长。

Q2. 一张长方形的金箔被粘贴慢慢地，所求粘贴前的边长是多少。

Q3. 将一张边长为 32 厘米的长方形金箔在连接处对折一次，转变成如下图附注的椭圆形。 所求w的值，单位为cm。

Q4. 都是由，将方形条带粘贴，所求粘贴之前的覆盖面积。

评论一区对作答，➥ 注意「小出国留学」VX，一起研究海外数学题。