Question

помогите пожалуйста!!
пятый класс математика​

Answer 1

Ответ:

1 Номер

$(3\frac{1}{3} + 1,25) : (2\frac{8}{15} - 1\frac{1}{6} * 2\frac{1}{10} )\\\\(\frac{10}{3} +\frac{5}{4} : (\frac{38}{15} - \frac{7}{6} * \frac{21}{10} )\\\\\frac{55}{12} : (\frac{38}{15} - \frac{49}{20} )\\\\\frac{55}{12} : \frac{1}{12} \\\\\frac{55}{12} * 12\\\\55$

2 Номер

1) $2\frac{2}{5} * (12\frac{3}{4} - x ) + 4,5 = 21\\\\\frac{12}{5} * (\frac{51}{4} - x ) + \frac{9}{2} = 21\\\\\frac{153}{5} - \frac{12}{5}x + \frac{9}{2} = 21\\\\\frac{351}{10} - \frac{12}{5}x = 21\\\\351 - 24x = 210\\\\24x=351-210\\\\24x=141\\\\x=\frac{141}{24}\\\\x=\frac{47}{8}$

2) $9,6 - (2\frac{3}{5} + x) : 1\frac{1}{15} = 2,35\\\\\frac{48}{5} - ( \frac{13}{5}+x) :\frac{16}{15} = \frac{47}{20}\\\\\frac{48}{5} - (\frac{13}{5} + x ) * \frac{15}{16} = \frac{47}{20}\\\\\frac{48}{5} - (\frac{39}{16} + \frac{15}{16}x) = \frac{47}{20}\\\\\frac{48}{5} - \frac{39}{16} - \frac{15}{16}x = \frac{47}{20}\\\\\frac{573}{80} - \frac{15}{16}x = \frac{47}{20}\\\\573 - 75x=188\\\\75x=573-188\\\\75x=385\\\\x=\frac{385}{75}\\\\x=\frac{77}{15}\\\\x=5\frac{2}{15}$

Я долго делал 20 минут