Answer:
1,000-25x=400+75x
Step-by-step explanation:
x=amount of days it'll take
1,000-25x=400+75x
Double the product of 4 and 7
Well a product meaning you multiply 2 numbers together. Multiplying that by 2 because it says double...

This should be your final answer below! Hope this helps
Number 1 would be the correct answer :)
Do you have a picture we can see?