SOLUTION: Fiona and Hoggy gain a kilo each every week. Fiona is currently 70kg, while Hoggy is 10kg. How many weeks does it take for Fiona to be TWICE as heavy as Hoggy? NOTE: I've asked

Question 757202: Fiona and Hoggy gain a kilo each every week. Fiona is currently 70kg, while Hoggy is 10kg. How many weeks does it take for Fiona to be TWICE as heavy as Hoggy?
NOTE: I've asked nearly all my teachers in my school and none of them have gotten the answer without using trial and error. I want to know how to get the answer by using algebra. Thank you :)
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Fiona and Hoggy gain a kilo each every week. Fiona is currently 70kg, while Hoggy is 10kg. How many weeks does it take for Fiona to be TWICE as heavy as Hoggy?
-------------
The difference remains 60 kg, so it's when Hoggy weighs 60 kg.
----
w = # of weeks
F = 70 + w
H = 10 + w
---
F = 2H
70 + w = 2(10+w)
70 + w = 20 + 2w
w = 50 weeks

RELATED QUESTIONS
Fiona is making a bracelet. For every 2 red beads, she is using 3 green beads and 4... (answered by Boreal)

Fred weighs 187 pounds but is on a diet that makes him lose 1.7 pounds per week. Barney... (answered by stanbon)

Fiona the fish is swimming 9/2 km every 9 minutes. How many... (answered by macston)

Fiona walks from her house to a bus stop where she gets a bus to school. Her time, W... (answered by Boreal)

Mindy has 2 more than 3 times as many rocks as Fiona. Together they have 54 rocks. How... (answered by jlshires)

Fiona has 8 cents totaling 50 cents. How many ways can Fiona have her... (answered by Alan3354)

Flora can finish her chores in 4 hours. One week, after Flora worked alone for 1 h, she... (answered by ewatrrr)

Jack has $50 in the bank and is saving $30 per week. Tom currently has no money but... (answered by addingup)

If it takes 1 week to create 4 seconds of animation for a movie, and your movie is 5760... (answered by rfer)