In 6 parts of alloy A, 5 parts are iron, and 1 part is chromium.

In 9 parts of alloy B, 7 parts are iron and 2 parts are chromium.

First, to compare the two alloys, get the same number of parts in total - we can use 18. So we have:

In 18 parts of alloy A, 15 parts are iron and 3 are chromium.

In 18 parts of alloy B, 14 parts are iron and 4 are chromium.

So combining 3 of A with 2 of B, we'd be combining 45 and 28 parts of iron, or 73 parts of iron, with 9 and 8 of chromium, or 17 of chromium, so 73 to 17 is the answer.

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