Last spring 12 birds ate 8 cups of birdseed in one month. If I am expecting 18 birds this month, how many cups of birdseed do I need?
Complete the double number line and ratio table to support your answer.
Simplified ratio of birds to cups: _

38+105= 143, 39+104=143, and you will find then adding the numbers on opposite sides, moving inwards yields the answer 138 every time. because of this, you’re going to multiply 138 times the number of pairs, which is 34. therefore, 34*138= 4692(i’m sorry if it’s the wrong numbers, but it’s the right concept)