Calculați 18 ore 12 minute 27 secunde - 9 ore 25 minute 42 secunde b) 4 ore 27 minute 35 secunde x 3 c) 21 ore 15 minute 32 secunde : 4 Va rog sa și explicați calculele
Răspunsuri la întrebare
Obs.₁: Se aplică aceleaşi reguli de efectuare a operaţiilor . de ord. 1 şi ord.2.
Obs.₂: 1 ' = 60 "
1 h = 60 '
a. 18 h 12' 27" - Obs. 12' = 11' 1'
9 h 25' 42"
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pas₁: 18 h 11' 1' 27" - Obs. 1' = 60"
9 h 25' 42"
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pas₂: 18 h 11' 60" 27" - Obs. 1' = 60"
9 h 25' 42"
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pas₃: 18 h 11' 97" - Obs. 60"+ 27"= 97"
9 h 25' 42" Se pot scădea "!
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? ' 55"
pas₄: 17 h 1h 11' 97" - Obs. 18h = 17 h+1h
9 h 25' 42"
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pas₅: 17 h 60' 11' 97" - Obs. 1h = 60'
9 h 25' 42"
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pas₆: 17 h 71' 97" - Obs. 60'+11'=71'
9 h 25' 42" Se pot scădea ' !
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pas₇: 17 h 71' 97" -
9 h 25' 42"
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8h 46' 55"
b. 4 h 27' 35" · 3=
pas₁: 35" ·3= 105"
pas₂: 105" - 60" = 45" 60" = 1'
pas₃ 27'·3 + 1=
81' + 1'=
82'
pas₄: 82'-60' = 22' 60' = 1h
pas₅: 4h·3+ 1h=
12h+ 1h=
13 h
4 h 27' 35" · 3= 13h 22' 45"
c) 21 h 15' 32" : 4 =
pas₁: 20h 1h 15 ' 32" Obs. 21h = 20h+1h
pas₂: 20h 1h 15 ' 32" Obs. 1h = 60'
20h 60' 15 ' 32"
pas₃: 20h 60' 15 ' 32" Obs. 60'+ 15'=75'
20h 75 ' 32"
pas₄: 20h 75 ' 32" Obs. 75'=72'+ 3'
20h 72' 3' 32"
pas₅: 20h 72' 3' 32" Obs. 1'= 60"
20h 72' 180" 32" 3' = 180"
pas₆: 20h 72' 180"32" 180" + 32" = 212"
20h 72' 212"
pas₇: 20h 72' 212" : 4= 5 h 18' 53"
Succes!