1) un intreg are 5 cincimi
5/5 = 1
2) X/10 = 2/5
X = 2×10:5 = 20:5 = 4
2 cincimi au 4 zecimi
4/10= 2/5
3) X/100 = 1/10
X = 100:10 = 10
10 sutimi sunt intr-o zecime
10/100 = 1/10
4) X/3 = 3
X = 3×3 = 9
3 intregi au 9 treimi
9/3 = 3
5) X/2 = 4/8
X = 2×4:8 = 8:8 = 1
4 optimi au 1 doime
1/2 = 4/8