According to Matt 5:27-28
'You have heard that it was said, You shall not commit adultery. But I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart.'

This being the case then why is the 7th and 10th Commandments the same? This cannot be correct and there must be another meaning which has been left out of Bible translations.

I personally think that the 7th Commandment was God's command to the Israelites not to mix racially with non-Israelites. This would give the word 'adultery' the true meaning like 'adulterate, 'adulteration' and 'adulterated' all of which have nothing to do marital infidelity but the weakening of a pure substance with an inferior substance .