Question

Jakim procentem liczby a jest liczba b,jesli:
a)a=4/5 i b=1/10 b)a=2/3 i b=2/25 c)a=2/7 i b=9/35 d)a=9/11 i b=27/100 e)a=2 i 1/2 i b=1 i 7/8 f)a=3 i 1/5 i b=1 i 7/25 g)12 i 3/5 i b=2 i 13/25 h)a=5 i 2/7 i b=3 i 7/10

Answer 1

Z proporcji

a)a=4/5 i b=1/10
4/5 - 100%
1/10 - x

x=1/10 * 100 : 4/5 = 10 * 5/4 = 25/2 = 12 1/2%

b)a=2/3 i b=2/25
2/3 - 100%
2/25 - x

x=2/25*100 : 2/3 = 8 * 3/2 = 12%

c)a=2/7 i b=9/35
2/7 - 100%
9/35 - x

x=9/35*100 : 2/7 = 180/7 *7/2 = 90%

d)a=9/11 i b=27/100
9/11 - 100%
27/100 - x

x=27/100*100 : 9/11 = 27 * 11/9 = 33%

e)a=2 i 1/2 i b=1 i 7/8
2 1/2 - 100%
1 7/8 - x

x=1 7/8 * 100 : 2 1/2 = 15/8* 100 : 5/2 = 375/2 * 2/5 =75%

f)a=3 i 1/5 i b=1 i 7/25
3 1/5 - 100%
1 7/25 - x

x=1 7/25*100 : 3 1/5 = 32/25*100 : 16/5 = 128 * 5/16 = 40%

g)a=12 i 3/5 i b=2 i 13/25
12 3/5 -100%
2 13/25 - x

x=2 13/25*100% : 12 3/5 = 63/25*100 : 63/5 = 504 * 5/63 = 40%

h)a=5 i 2/7 i b=3 i 7/10
5 2/7 - 100%
3 7/10 - x

x= 3 7/10 *100% : 5 2/7 = 37/10*100 : 37/7 = 370 * 7/37 = 70%