Odpowiedź:
zad. 1
[tex]a) \frac{42 + 21}{62 - 53} = \frac{63}{9} = 7 \\ b) \frac{7.4 + 1.44}{0.5 \times 8} = \frac{8.84}{4} = 2.21 \\ c)2 \frac{1}{10} + \frac{3}{5} = 2 \frac{1}{10} + \frac{6}{10} = 2 \frac{7}{10} \\ 2 \frac{8}{18} - 1 \frac{1}{6} = 2 \frac{8}{18} - 1 \frac{3}{18} = 1 \frac{5}{18} [/tex]
[tex]d)1 \frac{4}{5} \times \frac{5}{9} = \frac{9}{5} \times \frac{5}{9} = 1 \\ \frac{6}{7} \div \frac{3}{14} = \frac{6}{7} \times \frac{14}{3} = 2 \times 2 = 4[/tex]
zad. 2
A.
D.
zad. 3
[tex]140 \: km = 140000m = 14000000cm[/tex]
[tex]14000000 \div 5 = 2800000[/tex]
odp. B
zad. 4
[tex]s = 30km \\ t = 20min = \frac{20}{60} = \frac{1}{3} h \\ v = \frac{30km}{ \frac{1}{3} h} = 90 \frac{km}{h} [/tex]
a)
[tex]v = 90 \frac{km}{h} \\ t = 2h \\ s = 90 \frac{km}{h} \times 2h = 180 \: km[/tex]
C.
B)
[tex]v = 90 \frac{km}{h} \\ s = 120km \\ t = \frac{120km}{90 \frac{km}{h} } = \frac{4}{3} h = 1 \frac{1}{3} h[/tex]
C.
