7. Приведите дроби к наименьшему общему знаменателю: а) 7/30 и 29/84; б) 1/6 и 3/8; в) 11/35 и 7/45; г) 7/10 и 5/11; д) 3/20 и 1/16; е) 2/15 и 4/27; ж) 5/42 и 3/56; з) 29/60 и 109/126; и) 139/270 и 71/450; к) 17/104 и 59/338.

а) НОЗ = 420: \(\frac{7}{30}=\frac{98}{420}\), \(\frac{29}{84}=\frac{145}{420}\).

б) НОЗ = 24: \(\frac{1}{6}=\frac{4}{24}\), \(\frac{3}{8}=\frac{9}{24}\).

в) НОЗ = 315: \(\frac{11}{35}=\frac{99}{315}\), \(\frac{7}{45}=\frac{49}{315}\).

г) НОЗ = 110: \(\frac{7}{10}=\frac{77}{110}\), \(\frac{5}{11}=\frac{50}{110}\).

д) НОЗ = 80: \(\frac{3}{20}=\frac{12}{80}\), \(\frac{1}{16}=\frac{5}{80}\).

е) НОЗ = 135: \(\frac{2}{15}=\frac{18}{135}\), \(\frac{4}{27}=\frac{20}{135}\).

ж) НОЗ = 168: \(\frac{5}{42}=\frac{20}{168}\), \(\frac{3}{56}=\frac{9}{168}\).

з) НОЗ = 1260: \(\frac{29}{60}=\frac{609}{1260}\), \(\frac{109}{126}=\frac{1090}{1260}\).

и) НОЗ = 1350: \(\frac{139}{270}=\frac{695}{1350}\), \(\frac{71}{450}=\frac{213}{1350}\).

к) НОЗ = 1352: \(\frac{17}{104}=\frac{221}{1352}\), \(\frac{59}{338}=\frac{236}{1352}\).