An aged care office has staffing concerns about the number of calls they receive. If the number of calls per 5-minute interval exceeds 2, then a new receptionist should be hired. Over a particular 1-hour time interval, 29 calls were received. Assuming that the calls arrive in a Poisson distribution, conduct a hypothesis test with a 1% significance level to determine whether a new receptionist should be hired.

it is contrapositive

i could not see the question too well so check yourself again too . this is because i want you to get it correct.

< xcy ≅ < xby

step-by-step explanation:

in δcax and δbax,

so, δcax ≅ δbax (side-angle-side or sas)

since δcax ≅ δbax, we can conclude < acx ≅ < abx

in δacy and δaby,

so, δacy ≅ δaby (side-angle-side or sas)

since δacy ≅ δaby, we can conclude < acy ≅ < aby

now,

< acy ≅ < aby

=> < acx + < xcy ≅ < abx + < xby

=> < acx + < xcy ≅ < acx + < xby   (since < acx ≅ < abx already proved above)

subtracting < acx from both sides, we get

< acx + < xcy -< acx ≅ < acx + < xby -< acx

cancelling out < acx and -< acx from both sides, we get

< xcy ≅ < xby (proved)