Add and simplify

12 yd 2 ft 10 in
6 yd 1 ft 8 in
16 yd 2 ft 9 in
=

8 yr 9 mo 23 da
12 yr 11 mo 16 da
19 yr 7 mo 28 da
=

15 lb 12 oz
19 lb 15 oz
23 lb 7 oz
=

Step-by-step explanation:

1. Use the conversions 1 yd = 3 ft, 1 ft = 12 in.

  (12 yd +2 ft +10 in) +(6 yd +1 ft +8 in) +(16 yd +2 ft +9 in)

  = (12 +6 +16) yd + (2 +1 +2) ft + (10 +8 +9) in

  = 34 yd + 5 ft + 27 in

  = 34 yd +5 ft + (2 ft +3 in) . . . . convert 27 in to feet and inches

  = 34 yd + 7 ft + 3 in . . . . . . . . . add feet

  = 34 yd + 2 yd + 1 ft + 3 in . . . . convert 7 ft to yards and feet, then add yards

  = 36 yd + 1 ft + 3 in

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2. Use the conversions 1 yr = 12 mo, 1 mo = 30 da. (To be more accurate, we need to know the starting date of each time period.)

  (8 yr +9 mo +23 da) +(12 yr +11 mo +16 da) +(19 yr +7 mo +28 da)

  = (8 +12 +19) yr +(9 +11 +7) mo +(23 +16 +28) da

  = 39 yr +27 mo +67 da

  = 39 yr + 27 mo + 2 mo +7 da . . . . . convert 67 da to mo and da

  = 39 yr + 2 yr + 5 mo + 7 da . . . . . . . convert 29 mo to yr and mo

  = 41 yr +5 mo +7 da

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3. Use the conversion 1 lb = 16 oz.

  (15 lb +12 oz) +(19 lb +15 oz) +(23 lb +7 oz)

  = (15 +19 +23) lb +(12 +15 +7) oz

  = 57 lb +34 oz

  = 57 lb +2 lb + 2 oz . . . . . convert 34 ounces to pounds and ounces

  = 59 lb +2 oz

step-by-step explanation:

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