Question

Вычислите
1) 6dm7cm3mm+2dm 8cm 4mm =
2) 7dm5cm3mm-2dm6cm 8mm=
Помогите пожалуйста срочно

Answer 1

1dm=10cm

1cm=10mm

1) 6dm7cm3mm+2dm 8cm 4mm =

(6dm+2dm)+(7cm+8cm)+(3mm+4mm)=

8dm+15cm+7mm=8dm+1dm+5cm+7mm=

9dm+5cm+7mm=9dm5cm7mm

2) 7dm5cm3mm-2dm6cm 8mm=

6dm15cm3mm-2dm6cm 8mm=

6dm14cm13mm-2dm6cm 8mm=

(6dm-2dm)+(14cm-6cm)+(13mm-8mm)=

4dm+8cm+5mm=4dm8cm5mm

или

1) 6dm7cm3mm+2dm 8cm 4mm =6,73dm+2,84dm=9,57dm

2) 7dm5cm3mm-2dm6cm 8mm=7,53dm-2,68dm=4,85dm