折纸也能变回数学题？

友友们一一用金箔条折过金箔？对，幸运星就是。提议女学生们也带娃花钱花钱折金箔手工，培养他们的几何图形直觉。

今天把几道幼稚园几何图形题放置两兄弟练一练，学过矩形周长和km测算就能花钱。

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.

评论区对答案，➥ 关注「幼稚园成」，两兄弟研究者海外数学题。