A number of children are posing for a group picture. There are five 8-year-olds and four 9-year-olds posing in the picture.
How many arrangements are possible where the 8-year-olds and 9-year-olds alternate in the lineup?

6mm^3 or .6cm^3

      216

      /   \

  36     6

  /   \     /

6     6   6

factor trees are nice.

134.6 us dollars

step-by-step explanation:

1 us dollar = 1.33 canadian dollars

so, 150 us dollars = 150 × 1.33 = $199.5.

in canada, the money mitchell spent = 20 canadian dollars.

remaining canadian dollars with him = 199.5 - 20 = 179.5.

after mitchell returned to us, he exchanged the remaining canadian dollars to us dollars.

179.5 canadian dollars = 179.5 × 0.75 = 134.6 us dollars.