Consider this option (this is not the only way):
1. according to the condition 2345N is divisible by <em>6</em>, it means, that N is even number (0;2;4;6 or 8).
2. <em>6</em>=3*2, then the number 2345N is divisible by 3 also. It means, that the number (2+3+4+5+N)=(14+N) is divisible by 3, where N={0|2|4|6|8}.
3. using items 1 and 2:
(14+4)=18; only 18 is divided by 3, it means that N=4.
answer: 4.
Note also, that only 23451; 23454 and 23457 are divided by 3. Only 2345<u>4</u> is divided by 6 (2345<u>4</u>/6=3909).
Answer:
Check the explanation
Step-by-step explanation:
Following table shows the calculations:
Delta, X Southwest , Y X^2 Y^2 XY
45.96 38.76 2112.3216 1502.3376 1781.4096
46.8 45.41 2190.24 2062.0681 2125.188
47.93 15.7 2297.2849 246.49 752.501
51.78 49.58 2681.1684 2458.1764 2567.2524
52.17 44.34 2721.7089 1966.0356 2313.2178
47.36 18 2242.9696 324 852.48
Total 292 211.79 14245.6934 8559.1077 10392.0488
Sample size: n =6
Now
The coefficient of correlation is :
Join the centre O to the chord (let it be MN) & let OH be the perpendicular to the chord
OH bisects MN into 2 equal parts (each one is x/2)
OMH is a right triangle with one side =8, the second leg =x/2 & the hypotenuse = 12 (Radius)
Apply Pythagoras:
12² = 8² +(x/2)² ==>144=64 + x²/4 ==> x²=4(144-64) =320
x²=320==> x=√320 =17.88 ≈17.9
