-- After dog ate 1/2 of the collection, there were 29 remaining.
-- Just before dog came along, there were (2 x 29) = 58 cards.
-- That was after Dan added 5 new ones.
-- Before he added the 5 new ones, there were (58 - 5) = 53 cards.
-- When this story began, Dan had <em>53 cards</em>.
This question is worded slightly strangely but I believe I understand it.
To eliminate x, multiply the second equation by 8, so that it becomes 4x + .8y= 96
Then you can subtract 4x on the top by 4x on the bottom to eliminate it.
#2: 4 cans : $2.36 = 13 : $7.67 SCALE FACTOR: $7.67 divided by $2.36 = 3.25
Use the SF to multiply the missing information.
So 4 cans x 3.25 = 13
YOU CAN BUY 13 CANS FOR $7.67
#4: 2 eggs: 1 1/2 cups of eggs : 10 pancakes = : : 35 pancakes
SCALE FACTOR: 35 pancakes divided by 10 pancakes= 3.5
Use the SF to multiply the missing information
So: 2 eggs x 3.5 = 7
7 EGGS WILL BE NEEDED TO MAKE 10 PANCAKES
#6: 54 pounds: 1 acre = pounds: 12.5 acres
SCALE FACTOR: 12.5 divided by 1 acre= 12.5
Use the SF to find out the mussing information
So, 54 pounds x 12.5 = 675 pounds
THE FARMER CAN HARVEST 675 POUNDS WITH 12.5 ACRES OF FIELD
#8: 90 miles: 120 minutes (5 hours) = 225 miles : 300 minutes (5 hours)
SCALE FACTOR: 225 miles divided by 90 miles = 2.5
Use the SF to figure out the missing information
So, 120 minutes multiplied by 2.5 = 300 minutes (5 hours)
IT WILL TAKE 5 HOURS TO DRIVE 225 MILES
