Rotate one of them so the right angle is in the same orientation as the other one.
1. AB = DE
2. CB = FE
3. AC = DF
4. Compare the length of two known sides: cb and EF
CB = 3 and EF = 8
8/3 = 2 2/3 scale factor
5. Ab is side de. Multiply the length of ab by the scale factor:
4 x 2 2/3 = 10 2/3
6. FD = sqrt ( 10 2/3^2 + 8^2)
FD = 13 1/3
40
+5
+6
.03
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= 51.03
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(1)^3 /(3)^3
(1x1x1)/{3x3x3}
1/27 hope it helps :))