Question

пжж матем 4класс дам 10баллов ​

Answer 1

Ответ:

ответы на картинке!!

Answer 2

$\frac{23}{45}-\frac{12}{45}+\frac{21}{45}=\frac{23-12+21}{45}=\frac{11+21}{45}=\frac{32}{45} \\\\\frac{109}{250} -(\frac{16}{250} +\frac{63}{250} )=\frac{109}{250}-\frac{16+63}{250}=\frac{109}{250}-\frac{79}{250}=\frac{109-79}{250}=\frac{30}{250}=\frac{30:10}{250:10}=\frac{3}{25}\\\\\frac{57}{190} -(\frac{32}{190} -\frac{12}{190} )=\frac{57}{190}-\frac{32-12}{190}=\frac{57}{190}-\frac{20}{190}=\frac{57-20}{190}=\frac{37}{190}$

$\frac{35}{67} +(\frac{15}{67} -\frac{9}{67} )=\frac{35}{67}+\frac{15-9}{67}=\frac{35}{67}+\frac{6}{67}=\frac{35+6}{67}=\frac{41}{67}\\\\(\frac{42}{56} +\frac{8}{56} )-\frac{29}{56} =\frac{42+8}{56}-\frac{29}{56}=\frac{50}{56}-\frac{29}{56}=\frac{50-29}{56}=\frac{21}{56}\\\\\frac{203}{300} +(\frac{190}{300} -\frac{150}{300} )= \frac{203}{300}+\frac{190-150}{300}=\frac{203}{300}+\frac{40}{300}=\frac{243}{300}= \frac{243:3}{300:3}=\frac{81}{100}$