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5. ERROR ANALYSIS Describe and correct the error in finding the sum of the number

(25 x 10"] + 153 x 10" = (25+53) x 110' x 10°)
78 x 10"​

User Jalanga
by
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1 Answer

2 votes

Answer:

(25 × 10") + 153 × 10" = (25 +153) × 10" = 178 × 10" = 1780"

Explanation:

a) Numbers are miscopied: the numbers in parentheses should be (25 +153). Of course, the sum of these should be 178, not 78.

b) The common factor 10" is somehow expanded to 110' x 10°. It should be 10".

The sum should be ...

(25 × 10") + 153 × 10" = (25 +153) × 10"

= 178 × 10" = 1780" . . . . . correct sum

_____

Maybe the middle step is an attempt to convert to feet.

1780" × (1')/(12") = (148 1/3)' = 148' 4"

User Kresimir Plese
by
3.5k points