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Let's recapitulate the whole issue step by step :

The chemical shift of a proton can be quantitatively expressed as:
  1. the difference in the resonance frequency Dn between the signal nS of a standard, usually tetramethylsilane (TMS) for proton NMR, and the signal nPr of the proton in question. In other words
    DnPr = distance between sample signal and the signal of the TMS reference.
    Some additional comments:
    Since the resonance frequency is proportional to the magnetic field H,
    n = (g/2 p) Hz,
    where n is the resonance frequency, g the gyromagnetic ratio, p the constant pi, and Hz the component of the magnetic field along the z-axis
    it is common practice to describe the chemical shift not in units of the magnetic field, but in the frequency unit Hertz (Hz). However, due to the dependence of DnPr on the field Hz, chemical shifts described on this scale can't be compared between spectrometers of different field strengths.
  2. on the ppm scale according to the following relationship:
    d = (DnPr 106) / n0   ppm
    (1ppm = 1 10-6 (parts per million); n0 is the basic frequency of the spectrometer)
    On this scale the magnitude of the chemical shift of any given proton is independent from the basic frequency n0.
  3. in very old spectra on the t-scale (only for proton resonances, and very uncommon today) according to the formula:
    t = 10 - d
Memorize these relationships, and then give it a shot with these examples