Предмет: Математика, автор: владочка000

1.Для изготовления сплава взяли золото и серебро в отношении 2 : 3. Определите, сколько килограммов каждого металла в слитке этого сплава  массой7,5 кг. 

2.

Для изготовления42 кгземляной смеси использовали песок и чернозем в отношении 2 : 5. Определите массу песка и массу чернозема в этой смеси.

3.

Для изготовления смеси взяли чай двух сортов в отношении 3 : 1. Найдите массу чая каждого сорта в54 кгсмеси.

4.

Для изготовления начинки для пирога смешали курагу с черносливом в отношении 4 : 1. Определите массу каждого компонента в37 кгначинки.

 ПОМОГИИИТЕЕЕЕЕЕ!!!!!!!!!!!!!!!!

Ответы

Автор ответа: meruet
0
задача2
1)5+2=7 частей
2)42:7=6 кг- на 1часть
3)2•6=12кг - песка
4)5•6=30 кг -чернозема
задача 3
1)3+1=4
2)54:4=13.5кг
3)13,5•3=40.5кг одного сорта
4)13.5 другого сорта
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