Answer:
8th Person = 172 cm tall
Step-by-step explanation:
( a + b + c + d + e + f + g )/7 = 156
a + b + c + d + e + f + g = 1092 total size
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now they measured 8 people (a + b... g) + h, but we know the total size of the other 7 = 1092
a + b + c + d + e + f + g + h
( 1092 + h )/8 = 158
1092 + h = 158*8
h = 1264 - 1092
h = 172
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the 8th person is 172 cm tall