Ten large marbles weigh as much as 14 small marbles. How many large marbles weigh as much as 35 small marbles?
To get the answer we can use proportion
10 large ------------- 14 small
x large -------------- 35 small
crossmultiply
1035=x14
350=14x /:14
350:14=14x:14
25=x-its the answer
10 is 14 marbles
so 5 is 7 marbles
now 10 is 14 marbles
20 is 28 marbles
we got how many is 28 marbles
we know 7 marbles is 5
we need more tahn 7
7 marbles is 5
we have 20
25 is 35 marbles
answer is 25